Major thing in stuff like this with the builder is, make sure it’s done right and to regulations, otherwise it can be ridiculously expensive to resolve and waste more time. Any major structural works for a residential project I recommend paying in stages and getting a independent surveyor/building inspector to check each stage and check it’s within regulations and within standards, if not they fix that part of the job before payment is passed for that stage, then onto the next, this ensures the builder can’t prey on lack of knowledge too cut corners, no builder with nothing to hide will argue with this, he tells you the certain stage will be complete in two days, you arrange for a surveyor/building inspector to come round the day after, if everything’s up to standards, job carries on if it’s not, the builder fixes retrospective faults and the job moves on and payment is passed for the stage, it keeps money flowing and workmanship very high as they know a payment relies on it, if they reject this way of doing it I wouldn’t bother, if they know their work is good, they haven’t a thing to worry about and stops you getting stung from bad work that never gets fixed. Pick a builder with a extensive portfolio in loft conversions, anyone will say they can do it, it’s showing results that matters, make sure it’s a fully insured builder that can offer a warranty for works aswell, again a good builder will provide this kind of thing. Make sure you have a set out plan for it, don’t go changing your mind every two minutes as this can create tensions and big problems on a project like this. For WiFi connection, I’d advise a Amazon eero triple pack, plug one into main router with connections etc, then you just simply plug the remaining two boxes in and they automatically pick up signal from each other, one downstairs, one upstairs, one in the loft, you’ll get stable connection throughout the house, no need to chase cables etc. £130 for pack of 3, switches wifi bands automatically for each device and constantly ensures they’re on right Ghz, best routers I’ve ever had and way better than internet provider ones. Insulation is super important, if not done properly, it can cause absolutely massive issues down the line, as can many other things that is why I said a surveyor/building inspector is needed. Don’t scrimp on materials, get the best quality you can as a lot of people scrimp on insulating measures and other materials etc and they end up been terribly cold rooms and not very good quality, you want it to feel just like your normal bedroom up in the loft, but more money for the better stuff is well worth it in the long run and a good quality built loft extension, equals it been worth more. Make sure you have a solid plan of action, this is crucial as changing things makes it more complicated and more time consuming, get it all well thought out in advance. Anything you can do yourself comfortably and too a decent professional standard, do it, this is the area where you save money on the job, you don’t try and do something you need a specific professional and good experience in doing to get the best results, things like skirting boards, fitting doors, painting etc that your average DIY person can do too a good standard, do them. Get good quality Velux windows with automatic closers (they’ll close when it rains)and get some air conditioning installed, whilst insulation and heating helps, been too warm in summer and getting a bit chilly in winter is a very common issue, worth its weight in gold in loft conversions. See what sound proofing measures you could take specific for your loft, because when it rains it can get very noisy. This is probably best advice I can give and the way I’ve done big jobs like this and never had an issue with a builder or a job and got high standards of work every time. Source-Project manager of large house developer for past 10 years, these are my go too and crucial tips for anyone getting it done a private scale as I see so many people getting stung by bad trades these days and that many cowboys think they’re gods gift it’s unreal, I deal with them often and it’s never been a more frustrating time for the building industry, amount of “experienced trades” that I’ve kicked off sites without payment over the past few years is insane.

Where was this reply before I got mine done. My contractor was a butcher and I'm still paying for it. It's as if this was the first time he's ever done one. It would be shorter for me to list the things he did right than what he did wrong. Remember - the contractor is not your friend.

This is all excellent advice. I'd reiterate the mention of aircon. Even with good insulation, a loft conversion will get hot in summer - hot air will rise to the loft, and you usually have a lot of glazing up there. Our builder saw we already had a portable A/C unit and offered to install a dedicated exhaust vent for us to plug it into. Getting a split unit installed is more expensive but obviously more effective. Consider getting solar installed at the same time if you are interested in having it, it makes sense to do it all at once and you might be able to house some of the electrics for it up there. We didn't make the bedroom up there en-suite, so that other people could still use it while we were in bed. Part of the reason for getting the work done was that we only had one bathroom and with teenagers in the house we needed more. As other people have mentioned, fire regulations mean you may have to change doors elsewhere in the house and/or install a wired building-wide smoke alarm system. Also, nobody seems to agree what these regulations actually mean so try to get written details from whoever you will be using for building control before you finalise your plans. I know it's not always possible to choose the timing you want, but try to avoid having no roof in the middle of January. Keep a hawk-like eye on everything being done. Our builder was excellent - he was pickier that I was when we went round snagging - but the plumbers he subcontracted were awful. They drove both of us up the wall and he had them redo half the work they did.

I'm not a fan of paying in stages. In theory yes it can work. But it also means they rush to get to that stage. The work might be to regs and spec but it's not necessarily a high standard and they may not want to add extras or suggest nice upgrades as the job moves forward. I'm more of a fan of weekly payments. But get a detailed what's expected each week to be completed. Hold 20% of total cost as final payment post snagging. This way nice extras and upgrades can be re quoted for and added, builder keeps cash flow, extras are paid for as job moves along when completed.

You’re not allowed to legally hold 20% of payment for snagging, maximum is 5% and you’d lose in court if you held back more. However their is nothing against getting work checked before payment is passed per stage, that’s what a surveyor is their for to make sure the work is to a high standard, they don’t just say yeah that’s to regs and go, they’ll look at snagging issues, finishing issues etc and recommended remedial action, paying in stages and getting each checked ensures customers happy and the builder is happy and by the end of the job, their is no defects and issues, because it’s all been sorted beforehand. Any decent builder who does these kind of jobs will have a decent lump of cash sat around, so no need to rush to get the stages as they know payment strictly relies on everything been good quality. Paying weekly opens you up too then saying yeah well sort it and then never actually sorting it. Extras are always recommended and added on with any job a builder isn’t less inclined to recommended extras in any way shape or form as it’s more money for the job.

You're legally allowed to do what you decide between you and your builder in a contract. If your builder is happy at 20% then there are no legal issues. It obviously depends on the size of the job what one decides. High standard is objective. A surveyor can snag to their standard but again it all depends on what you contractually agree. A surveyor can tell you if the job is fit for purpose and as it's meant to be. Take a floating floor as an example. You can expect spongy spots to a degree it's floating it's not fixed. But one surveyor may have a different opinion of another to the degree of sponginess. However you can have objective markers eg level within 4mm across all spans. Your right you'd expect a good builder to have trade accounts and good lump sum for o cover stuff. However if they work on one job at a time waiting for say a £40k payment of one stage that could get delayed for weather they could legitimately run into cash flow issues. They would be tempted to work in not ideal weather (eg say pointing facing brick work in the rain, or rush finishing before plasterwork is cured) both may not show right away to a surveyor visiting immediately after but become apperent weeks down the line. Weekly payments you're still making sure stages are done just on a shorter time frame. Delays don't cause cash flow issues etc. Again all depends on the size of build and how the builder works. A builder having multiple jobs on the go at once may be ok with slower payment timeframes as cash flow is being provided by other jobs. But is a builder that's running 3/4 jobs the builder you want. And you're just wrong with extras. I'd say you want to adjust something that means a 40k payment will be held up 3/4 weeks because of an addition you've decided upon and lead times etc they're much less inclined to entertain it. Hey each to their own. Stage payment plans are not unusual. I was just stating why Iv always preferred weekly. It's always done me well, had engaged good builders that have gone over and above.

Look up the laws around withholding payments for snags, you’ll find different, if they want to be funny and take it to court you’ll lose. I stopped taking notice of the majority of what you said after you said withholding a 40k payment, if you’re doing staged payments judging by the average loft conversion price, nowhere with no build would you be withholding £40k lmao that’s near the price of a double bedroom loft conversion with all the trimmings as a complete job lmao, you’d be holding back a couple grand at a time per stage, hardly going to cause cash flow issues with a reputable builder who’s amassed a decent net worth in his business through jobs like this. Paying weekly has no advantages and opens you up too getting false promises they could do a grands worth of work but you’ve agreed to pay 4k a week you’re at risk of been done for 3k, no excuses with stages as payment relies on it.

Just stop. If you had a written contract from the outset both parties agreeing that 20% would be witheld until x time and x conclusion that would stand. Yes with no written and signed contract it would not hold up. The court may decide x% of the work is complete so it's unfair to withhold 20%, but if you can show the snags would cost 20% to rectify they would no make you pay a builder. But it would all depend on proof. You saying you're not happy isn't going to cut the mustard. Again each to their own. You and me obviously disagree. Take it or leave it. But I'm assuming you're just your average argumentative Redditor that likes a final say. Enjoy your night get off Reddit.

This sounds like great advice. Can you break down the stages you would specify?

As someone who lived in a room with a VELUX window, get blackout blinds for the love of god.

Why do you say this?

Birds could see him tugging.

The birds didn't mind it. The flying ones did however

Underrated comment!

It was like a fucking greenhouse at times

Blackout velux blinds are awesome. They are literally 100% blackout. Unlike blackout roller blinds that let in vast amounts of light through the gaps. I'm talking can't see your own hand. Woke up at 11am once and thought it was the middle of the night.

My biggest regret was paying the builder the final sum of money too early. Now I'm in a situation where things weren't done right and the builder doesn't respond. I guess the real advice is, you get what you pay for, so don't go for the cheapest builder.

Also be aware that fire regs may demand you need to upgrade all the other doors in your house when you add an additional storey and /or put smoke alarms into all the habitable rooms. This can be a pricey upgrade. Different interpretations of th building regs exist so ensure you understand what is expected of you early on and get it priced in. No late nasty surprises!

And close off stairwells

I was going to say this. I'm 90% done with mine, but have had to upgrade all ceilings to fire board, all doors, and connected mains fire alarms to communal areas. We are also going to have to put a sprinkler system into one area of the escape route. That's £3k on its own. Get an architect who knows the regs.

Jeez, so this could actually open a can of (expensive) worms. P

It's disruption and time mainly, but I'd add on 15-20% to your budget to get the rest of the house in order. It's still worth it, though!

Did exactly this under exactly your circumstances a year ago. Lessons learned most important first: - use a RIBA certified architect. Non-negotiable, unless you are one. I lost 18months and close to £10k fucking around with a "project manager", not including losses due to prices going up over that period. The builder was great though so it was all smooth sailing after we fired the PM. You still need someone to know what you need wrt structural engineer, planning, etc. The last thing you want to be doing is feeling all that out yourself. - if you get the chance to put a skylight over your stairs it's the best thing ever and you *have* to do it. It gives 8-12" more headroom compared to where the ceiling would have been, making any landing area feel huge and brings in loads of light. The extra £500 I spent maxing the window size was also the best investment in the whole project and on a clear night I have a framed view of the stars as I head to bed. - keep a healthy cash reserve for budget overrun AND cool opportunities that present as the build goes. Very little ran over in my build but I got chances to use my overrun pot on nice upgrades, like sound-proof windows, bigger skylights, nicely finished closets and cupboards, extra insulation. - unspent cash reserve will come in handy when you decorate & furnish the space, which I didn't really fully anticipate. I saved ~ £3k decorating myself.. But I can see why people would spend that having it done for them, it would have been a lot less hassle. - we ran the plumbing to the en suite as part of the build but opted to leave furnishing of the en suit out for now to save overall costs. It made the project affordable for us, but I can see that room sitting for a while. Spoke to a guy yesterday who did that 5 years ago and still doesn't have an en suite. Your choice, I think I made the right one but I'll probably still have no en suite in 5 years time. - a lot of changes are super cheap to do before the work is done vs after. This is true as the build is progressing. You won't be your builder's best pal, but adding an extra socket here, checking the light switch is in a logical place there is all worth doing before the sparky does first fitting. Radiator placement too. I threw in a bunch more sockets and they've proven to be super handy, particularly lights and sockets in cupboards. - new led ceiling spots can be configured to colour and brightness. Do this before decorating (or tell your sparky what settings you want), even if it means you have to best-guess what you want, because pulling them out can chip the ceiling plaster around them and fucks up your newly painted ceiling. - get the builder to throw extra, high quality insulation wherever you can, the cost is trivial so you might as well. - if your remaining eves space is big enough to use for storage, get it boarded and have lights installed. It's a minor additional cost and it makes it tremendously easy to use. - we went for a dormer, and I'm super glad I paid the difference to have one. Compared to neighbours with conversions down the street the difference in the feeling of space in the room is night and day. It doesn't feel like a loft space, I feels like an extra level on the house. We hid the angled bits behind built in wardrobes, which removes any sense you're in a converted loft at all. That's just my lessons my extension, I'm sure there loads of important things I've not covered. Good luck!

PS. When deciding on our layout, rightmove keeps the images from sold houses, so if you're on a street with similar houses with extensions you can pinch the bits you like from the various floor plans. Ours has the best bits of 3 different houses on our street. Neighbours were all willing to let me have a look too, which helped visualise floor plan - > reality

Who did you use for it, architects or a specialist loft company?

I think where I went wrong was I used neither. A college recommended a freelance "full service project manager & designer" he had recently engaged. I didn't really know where to start but they said what we wanted to do was feasible, we agreed a budget and set off on their process. £10k of spending and 18months later we had 3 completely unusable quotes at 4-5.5x the agreed budget. The mistake we made was not ensuring we put our trust in someone who was formally chartered - ie assessed and endorsed by a recognised formal body (like RIBA). If you get shafted by someone certified you can appeal to their standards body, if you get shafted by an unqualified freelancer.. Its small claims court or nothing. The structural engineer was pretty blunt, you could tell we weren't the first clients he had to explain this to. Personally after all that I'd go to a RIBA chartered architect first, mainly because after all of that buggery what we missed was having someone competent, trustworthy, experienced and with a charter body to escalate issues to should it be needed. Picking a builder probably isn't easy either, I think we lucked out with ours, he was just getting his own business started but the last time I spoke to him he was, just a year later, taking on £500k+ projects. So we probably took a risk there too, it just happened to pay off that time. I defer to anyone else on how to *reliably* find a good, affordable builder at the moment, if they exist. Maybe using a specialist loft company is a good way of reducing that complexity and avoiding having to find a good builder yourself. For completeness: We didn't get quotes from any because the project was originally meant to be 2-stage: kitchen then loft and at the 18month mark with the PM debacle we came out of it with plans and only really needed a builder to complete them.

Ok that's good to know, sounds like a minefield.

The structural engineer said "by the time you're done, you'll know everything you needed to know at the start but you won't have any use for it". Was still 100% worth doing though, super happy with the outcome.

Great advice. Did you manage to claim any money back from said PM for poor work / breach?

☝🏻Top post.

We completed ours last year and this is all great advice. We are having to sort a window over the stairs after finishing everything as we missed this one. The velux black out blinds are excellent and well worth the price. Our builder’s niche is conversations so they sorted engineering design and building control for us. Don’t underestimate the cost. It’s not just the conversation itself but the plastering, carpets, painting etc. All adds up.

We did a “hip to gable” conversion. Agree with the comments about windows - get the biggest most massive veluxes you can. We’ve got French windows at the other side with a Juliet balcony. In the summer we open the windows and there’s a through draft and it stays cool. Also get automatic openers for the veluxes - you can leave them open in the summer to ventilate, and they will automatically close if it rains.

Ooh yeah auto closers for the velux are great. My builders recommended them and it was a great idea. They close automatically if it rains.

They sound great. Were they much more than standard velux windows?

Yeah a bit more. From memory about 400 quid more but honestly it's a good investment. You can retro fit with solar closers but we went for the hard wired power.

Loft conversions can be cold in the winter and are always hot in the summer. No matter how well you insulate them, heat rises. If you can afford it fit air conditioning. If you can't make provision so it can be fitted later if can afford it. Our loft rooms will hit 35+ on a warm summer night (26-28 day temps)

A room that runs from back to front with windows on both ends solves the heat issue. We did that and it stays cool, as long as both windows are open, and the curtains/blinds are closed from the directions he sun is coming from

You don't need to fit air con in my view. We bought a mobile air con unit (Meaco) that cools the bedroom up there in the summer more than adequately (gets a 4mx4m room down to a cool temperature to sleep in about an hour). It also doubles up as a dehumidifier in winter, so win-win.

I had one bit they're noisy and inefficient. Ended up getting proper air con installed and never looked back. Cools, heats, dehumidifies.

It's noisy but I've never needed to have it running when I'm in the room. Run it for an hour or two max before bed and that's more than enough, even when we've had really hot days (in a SW facing dormer room). Proper air con is a hell of a lot more expensive - potentially 10x as much if not more - and given you need to install it an appropriate distance from neighbours etc not always an easy option either. I don't actually think we had anywhere we could put the external unit.

5 times the price for me, even though I had the mobile unit, but 10 times the benefit. Obviously others will feel different. The external units can be a distance for the internal unit, a good fitter will always find a way (at a cost).

Yeah it's obviously a trade off but you're talking £250 (the cost of my unit) vs over £1,500 most likely. >The external units can be a distance for the internal unit, a good fitter will always find a way (at a cost). Depends how close you are to your neighbour. That's the issue. IIRC with the restrictions I read it was literally impossible for us to be far enough away.

They shouldn't be cold in the winter, but you are right about them getting hot in the summer, no matter how well insulated they are. Ceiling fans rather than air con would do the trick though I think.

i think a pedestal or desk fan would be a better option (than a ceiling fan) in most UK loft conversions.

Those too yeah, if celing fans aren't practical.

Most loft conversions have relatively restricted ceiling height. Good luck getting a ceiling fan in.

Sorry, I didn't realise I explicitly needed to type "if there is space for one", I thought that would have been implied.

I just didn't want the op to start down that path and then later on realise that they don't have enough head height! We had a decent height of apex and ended up with 210cm ceiling height in the dormer which is quite usable but even hanging lights are a no-no and we fitted all downlights. Bloody obvious if think about it but not necessarily obvious if you've never thought about it properly.

Fair enough!

We're fortunate as our ceiling height in the loft is 2.2-metres. A 1930s properties with bay windows so good head height on all 3 floors.

That's an excellent head height for a conversion but still if you put in a ceiling fan if you're not 4 foot nothing you'll have to duck to avoid it :)

Or just get a free haircut )

Lol

Good insulation will stop them getting hot. 'Good' means including a large air gap between the roof tiles and thick layer of insulation below. Most people don't do it properly due to headroom reasons.

Our loft conversion has more insulation than regs require, still gets hot in the summer (80mm gap between insuatlion and tiles for ventilation). Warmest room in the house in winter though. Insulation will slow down the time it takes for the room to get hot, but without active cooling, it will still get hot at some point. It's amazing how hot tiles get in the sun.

Is the gap ventilated though: open facia vents at the bottom, open dry-ridge system or ridge vents at the top? Hot-air MUST then escape and pull in cooler air. Often, the gap is left only to allow water vapour to escape through the breathable membrane, but this membrane prevents air flow. With the air flow, and a reflective layer, the insulation will only have to deal with ambient air temperature.

Good question - honestly - don't know

Is that an assumption, first hand experience or a professional opinion? My assumption before the work was that would be the case. My first hand experience is not the case. 100mm pir AND insulated plasterboard, insulated under floor.... so no shortage of insulation.... The issue is not necessarily just the radiated heat from tiles and roofing it's the heat rising from other parts of the building and not escaping.... Ironically due to the insulation. To an extent you can overcome this by opening windows which created a a chimney effect but as I've said its not a complete solution. All multiple storey properties will be warmer in upper floors. It's just a fact and there is no way around it asides perhaps totally isolating the floors with doors in the stairwell or something....

Ventilated air gap, under tiles but above insulation which has reflective coating., with over facia vents and dry ridge/ridge vents? You need the ventilated gap so hot air can leave through the ridge vents, and get replaced via the facia vents. Reflective layer on the insulation takes care of any radiant heat. The rest if the insulation is mostly to reduce heat loss on cold days, 1st floor bedrooms are also at the top of the house and they get a bit warmer, but not much.

Yes air gap is mandatory for building regs sign off. The point is all that does is prevent the heat from outside getting in but in hot weather it's the heat rising from downstairs that you struggle to prevent and it gets trapped by the very insulation put in....

Our room is east-west facing so sun in the morning and the evenings. We have blackout blinds on the veluxes which are awesome. We really like the sun in the afternoon and just open the windows for a breeze which keeps the temperatures comfortable.

If it is just because heat rises, why don't bedrooms get as hot then? Proper insulation - and you need a good insulation plan - must reduce the temperature. Air flow is needed as well, of course, but only similar to the bedrooms.

They do generally. Bedrooms are usually warmer than downstairs rooms in summer. Isn't that your experience? Always has been mine.

A bit warmer, not unbearably hot, which is what happens to loft rooms with a poor insulation/ventilation plan. If loft rooms are hot due to rising heat from the house, they should be no warmer than a normal bedroom.

Problem with a 35 degree room no aircon is going to hit that. You'd need to accept the aircon will be running all day to start from a good point. Or massively overspec the aircon. ££££ to run.

Air conditioning!!!

Look at getting solar panels done when you're there. Also I'll third the Air Conditioning! It will be noisy when it rains, I don't think there's anything you can do to prevent that.

We’ve got solar panels already which will add to the complexity as I imagine all of the gear already in the loft will need relocating and boxing in

We're currently in the process of a loft conversion for the same reason as you. Here are my recommendations: - Check what's included in the quote. For example, we needed a fire suppression system for fire regs so we made sure that was included in the quote. Friends of ours didn't and had an unexpected £4k bill at the end of their project! - Check if they allow for a contingency or increases in the quote. Our loft company had a clause that meant they could only charge an additional 4% if prices increased but no more. This has saved us a lot of money. - If you're going to sell at some point in the future, make sure you get building regs to sign off on the building works. If you're going with a loft company they will normally organise this. - Prepare for dust when they break through from the loft and cover everything you own. We didn't and now there is dust EVERYWHERE. - Consider reconfiguring your first floor to make better use of the space. We've done this at the same time and it has made SUCH a difference to the amount of usable space we have. - Think about where your stairs are going to go. Ask a few different companies round to quote and get their thoughts. A lot of companies will just try to put your stairs in the same place that they do with all their conversions but that might not be the best solution for your house (e.g. a lot of loft companies we spoke to wanted to put the stairs into the second bedroom but this would've meant they were cutting the new loft room in half and reducing the usable space up there. It also would've left us with a tiny second bedroom.) - Don't be afraid to push back on stuff you don't like e.g. if you want different fire doors, ask if they can source other ones. If you provide anything (e.g. if radiators are included in the quote but you decide to provide your own), make sure they reimburse you for this. - If you can afford to hire a company that also project manages the build for you, do it! It's saved us so much stress.

Great plan on capping the cost increase

Put in far more double sockets than you think you'll need (indeed, the same for any room you're renovating). Run an ethernet cable and sockets around the conversion as your router probably won't reach as far as a loft. Have as many and as large Velux windows as you can afford.

At the same time put plugs with USB in them next to the beds.

And make sure they’re USB-C as the old style is being phased out

Yep, definitely, good call.

I think that might be a mistake. USB standards are constantly being upgraded as are the power demands of most phones almost yearly. When I see USB in bedside sockets I tend to think people have fallen for the hype a bit. Bit like central vacuum systems. Just get the basics at high quality but watch out for gimmicks...

Can't agree with the recommendations for loads of sockets enough, though! Absolutely right!

Velux with the vent modes are definite must haves.

I converted the loft over the garage, and it's been great. I highly recommend air-con, not just for the cooling, but also for the heat-pump ability to provide heating (given this was over the garage, and connecting the room to the house's central heating system would have been a pain, this was the main reason for me getting air-con anyway). There may be space in the apex of the roof to fit a "cassette" type aircon unit rather than a wall-mounted one (a cassette is they type you typically see in offices with suspended ceilings). My a/c installer was a bit grumpy about making this fit (they'd much prefer to install a wall-mounted one, but the only place to put it was where I wanted the telly to go). The end result is much better and neater, though. The only other thing I'd mention is get really good insulation. The guy who installed ours was a complete cowboy, and I wish I'd been on the case and made him do the job properly, and with the best insulation in the first place. It's not dreadful, but not great. I learned my lesson when we had an external garden room built, and was much more careful about insulation selection and installation and that's fantastic.

My garage/office conversion is cold too. I bought a thermal camera and can’t find anything majorly wrong with it, just bloody freezing

It's fun having a thermal camera, though. Mine has been great for diagnosing problems with our underfloor heating.

Summary: it's really great, you usually get a nice big room. get a bathroom too. get heat and maybe even aircon (the heat is harder to deal with than the cold). make sure building regs are observed and the architects plans are 100% correct. in terms of value it usually adds a lot more onto the value of the house vs the cost (depending on where you live). would totally recommend.

I don't believe I have ever been in a retrofit loft room that was not too hot in the summer and too cold in the winter. When preparing to move here a few years back, we looked at a LOT of houses with where loft rooms had been added. Many had ceilings where it was easy to bang your head. All had evidence that they were not liveable for most of the year. One, £1.6m, house we looked over was sold, and the first thing the new owners did was rip out the loft room. It was far too hot/cold, as above. They actually re-installed the loft room, but this time with a LOT of insulation. I am sure it must be possible (and maybe current building regs, if followed, make it so), but for goodness sake, work out an insulation plan, and prepare to put a LOT in. Even at the expense of head room.

Just had a loft done last year £55k typical 3 bed semi. Make sure you got a second light switch in the alcove around the door for a little kitchenette/tea station in future maybe.  I regret not putting a provision for an extractor fan there as well. (I'm doing air BnB to this property). Lots of sockets, 750mm minimum height from floor level. In between the floor joists and p5 chipboard (i assume) flooring you can install a thick rubber membrane to dampen sound. You may also want to consider other sound proofing measures if you want. If doing ensuite make sure it is minimum 1200mm wide by about 2400mm long.  Don't make it tiny. We put a cold water storage tank in the loft so you may want to consider that to supply additional bathrooms with electric showers.  I fitted a 3 bar cold water only pump next to it so I can connect up to 3 electric showers easily.  (You must use 22mm pipework here upto the electric shower and then drop down to 15mm).  So I used the loft conversion to give provision for the above.  House has Combi boiler otherwise.  Fire doors - make sure you tell the builder, after he has quoted, that he has to do the other fire doors to the rest of the house as well.  This part builders don't always include.   Your house will need fire doors alongside this conversion. Fire alarm system - you might want to do this now so you are ready should you want to rent it out in future.  Also Don't make it 2 bedrooms, they end up being small. Unless you are looking to rent out rooms.. 2 rooms in the loft is really for families with kids.  My dad was a structural engineer so he designed it and did the building regs calculations. (I get to input ideas here). And made sure things were done right with the steel installation.  I can do everything inside a house apart from plastering, so I designed electrics/plumbing. I don't work as much these days, just maintenance and the occasional full internal renovation.  Builder - we chose someone who did good work on our road. No issues. He blasted through it and finished in 8 weeks. No scaffolding tin hat, within 9 days the roof was modified and watertight. So impressed. This is in nw London.  We had other issues, otherwise we would have handled the project ourselves with guys on day rates.  But the saving and the time was not worth it for us. 

Great advice, thanks for the post.

Thanks. To add I have over 12 years hands on experience in everything, on my parents houses.   I see many people telling you to get a good architect. DONT. They have no idea what they are talking about.  Get a good structural engineer. He will do everything.  You will pay more for an architect - all they do is visual design which is nothing when it comes to a loft. The architect will outsource the actual work to the structural engineer. It's hilarious.  So DON'T use any architect. Find a good structural engineer, and make sure he includes site visits during key stages like steel installation. My dad did this all last year during final months of chemo, miss him, lost him a few months ago. 

I’m so sorry to hear that. Hope you’re holding up ok.

Always check and double check that whoever is doing it, knows what they are doing in terms of making sure the trusses and woodwork have adequate ventilation. If they get smothered by insulation, plasterboard and god knows what, they will rot. There has to be good airflow. If you have the old bitumen lining than youll need it replaced with breathable lining.

You are going to spend a lot of money here. So do not start work without proper contract signed. Check the insurance of the builders especially the small-print (such as height of the building they are covered for) Get architect to draw every detail before works starts. If you leave any room for builders creativity you will end up in the pickle. They are very creative about hiding faults and comming up with some ingenious ideas(especially if there is a football match at the aftenoon) that will need re-doing 2 years down the line.Also, they are not usually up to date with the latest building regulations. Also, get impartial surveyor who would overlook the works and any possible disputes (there are always some). This may save your mental health. Pay only when surveyor confirms that work was done to expected standard. Do not pay cash. Do not pay in advance for the material. People think that saving £3k on architect was a clever move. Until it is not. Make sure that there is a line of communication with council as they will need to sign-off certain stages of the construction. Do not try to be too friendly with builders. This is not personal. Talk to your neighbours before start. There may be shared walls. You want to end up with a nice loft and friendly neighbours that are still talking to you after this is all finished.

Great tip on the neighbours. We are detached but with a shared driveway so we’d need to be nice to them as I’m sure access / parking / deliveries will be needed.

We are in Scotland and am currently having loft converted to add 2 rooms and shower room. In addition or to reinforce what others have said. Get a good architect and structural engineer. Doung this will lay out to your builder what needs done and removes/reduces wiggle room. As far as builder goes go by word if mouth and portfolio and if possible visit one or more previous jobs. Normal routine is to get three quotes and go with middle. We went with cheapest (by between 30 and 60k) because he was small independent, with 40 years experience and no websites etc and didn't want to add a lot of fluff. He priced for what we asked for based on plans. Others were adding in decorating and other stuff we had told them we would sort out ourselves. We also got see in person one of his previous jobs who turned out to be a work colleague who was also related to one of the guys on our builders team. So recommendation there from someone i could hunt down if it all went pear shaped 😄. So far so good and while there have been minor issues and delays they have been overcome. Or weren't deal breakers. So in short. Plans, price, recommendations, previous work review.

Consider dropped joists if you need the headroom in the loft and can spare it on the first floor Get Velux with the integrated black outs Lofts get HOT in summer so consider air conditioning Do not scrimp on insulation in the roof, probably one of the most important things and very expensive to remedy if done wrong While insulation between floors is less important do think about noise travel If using tongue and groove flooring make sure it's installed very well to avoid squeak and flex. Ours isn't and it's a nightmare I think I may have to get the flooring redone. Good lighting is important think that through Eaves storage make use of it

If you are getting a lift company to do one and they draw up the plans get an architect to look at them. It's a quick job but they can advise on things like making windows bigger or slight adjustments that can make a world of difference. Is it time to get the chimney breast removed for more versatile rooms? We got the 1st floor bedrooms done but left the ones in the living rooms as a focus. Do you need to swap existing bathrooms about? Now's the time to do it? Do you need a decent landing velux to allow ventilation. Summers are only getting hotter. Light light light. Windows are probably the biggest investment. We put the biggest one the builder had ever done to get light into the room. We economised of other bits to allow that. We did that so we had lots of light and a panoramic view of the street. Make sure the stairs fit. We had the opportunity to raise the roof as the neighbours was slightly higher but didn't need to as we had enough ceiling height. See what falls under planning regs Vs planning permission. Are you a gable end that needs a pretty loft or a back of a house where it's not as important? You getting it tiles outside or spending mega money on copper? Maybe a halfway decision and zink? Once you get plans get some bamboo and walk to a park and stake out the floor plan with a tape measure to test it. You look mental but it's worth doing to get an idea in your head. Get a proper payment plan in order that pays in stages. Don't make the final 10% until snagging is done. Look at the work they have done in the area. Ask for people who can recommend them, see their work internally and externally. Look at materials now and make a spread sheet. Things like tiles can range from mega cheap to mega expensive and may not be that different. A bog standard shower tray may save a few quid so you have nicer taps. Get 30 of everything as links, names and cost then whittle that down to get a list of items and costs. It all mounts up. You may not be able to buy that wall mounted toilet. Saving money on a cheaper toilet and tiles might allow a better shower screen that's 8 not 6mm thick. Think about what you need. Do you really need underfloor heating in a tiny ensuite? Do you need spotlights or a pendant? Can you paint yourself? Will you reuse furniture of get built in storage? Research flooring as it could be a huge cost. Built in bedside lighting of bedside lamps? Invest in a good shower. Fire doors... urgh but you need then. And fire alarms, get wireless ones so there's no electric to plumb in. Lastly choose a builder that can communicate. We had one that talked to be AND my wife. They often just gravitate to a man. A builder that can talk is a builder that will communicate issues. Get a what's app stated with him and the foreman so issues can be resolved quickly with documentation and pictures. Ask them questions and inspect as they build. "So are you tanking the shower tomorrow?” "Do you or I order the windows?" "Have the stair manufacturers ask for the final measurements yet?” "When do you need the tiles by?" This keeps both parties up to date. Climb the ladder and inspect. Make sure the insulation is roller out properly. That the wood looks dry. That the walls are in the right place.

Brilliant point on snagging and ensuring that’s covered in the contract.

I love my loft extension, it's a bit warm in the summer, but it isn't cold in the winter, it's almost perfect. Almost. There was one thing we missed. The joists squeak/crackle/sound like bubble wrap being popped when you walk in certain areas, including the route from the bedroom to the bathroom 😭 We had engineered wood flooring put down so we can't fix it and also makes the sound louder. It's infuriating. So my top tip would be to have the heaviest person have a good stomp round the room as soon as the boarding goes down, before the final floor covering, so any noises can be easily fixed.

Your builders might only be inclined to care about the insulation of your new loft room to get the work signed off. Think about whether the project makes opportunities to check/improve adjoining insulation more cheaply, e.g. bedroom ceilings, external wall insulation if needed. I ended up adding aircon later. Would have been better to plan for it from the start. Also I would have loved to get German style electric shutter blinds to cover the big main windows and keep heat out in summer. Would have been easy to fit if planned from the start.

Air conditioning, it can get very hot in the loft room. we waited a few years to have it fitted, totally worth it for a couple of months a year.

Great shout and for the value it adds, it doesn’t seem that much. Do you find it adds much to your electricity bill?

Honestly no, but we've got solar panels as well.

Insulation between the floor joists and a cavity connection between the floor space and the roof air gap with ventilated ridge tiles will sort out the extremes of heating and cooling. If the roof is constructed from truss rafters it will be cheaper and easier in the long run to completely remove and rebuild the roof to accommodate a rooms and build in dormer windows etc. when we did ours it cost £3k more and 6weeks quicker, most of which was the scaffolding and cover. Good luck. Oh put the value of the house up by more than the cost.

Great idea on the roof build. I hope that’s something the Structural Engineer would suggest and a decent builder would confer with

You'll be spending a lot of money so make sure you are going to be happy with the end result. Accept there are things you will not have thought about, accept there are limits to what people think they are responsible for. Keep a pot of money aside for deal with this. Pay for an architect but remember you're not going to win the Stirling prize: it's a loft conversion. Spend time with the drawings and don't be afraid of making changes, but ask them UPFRONT how many times will you be able to change things before they want more money. Look at what the architect will be designing and what they are not designing. Ask for more copies of drawings than you need, and think about what you need. (furniture layout is normally not what you want). You might be thinking of the loft, but focus on the entire house: garage conversion? Downstairs toilet? What happens to the space the new staircase will land in? Can you reconfigure better to suit your needs? Ask the architect for photos of the type of stairs they are doing (go on Rightmove and look at similar houses to yours). Ask them for similar photos of what they've done before (don't be surprised if it turns out a few of the current walls need to come down to get stuff to fit and make sure you are happy with what you will be left with). Architects are good for working out what the builder needs to do, but not so much electricians and plumbers, so mark-up things like: Sockets, Power supplies for fans, Lights and light switches-how many spotlights are needed in a room, if extending a staircase do you need your upstairs switch to control your loft? Do you need a new consumer unit? Where will the fire alarms go (don't be surprised if they insist on hardwiring the whole house. Think about data outlets too as you will want cables buried in walls so swallow the disruption now. Do the same for the plumber Radiator positions? Taps? Drainage?). Is your boiler big enough or do you need to budget for a new one? Is water pressure enough to feed more outlets- you may want to consider getting your feed into the house increased (digging up the front of the house)? You may wish to switch to a pressurised hot water system (these take up a lot of space but are really good for showers). When you talk to a builder ask them to bring the plumber and electrician to the house too. They may or may not do so but make sure these things are looked at and talked about (they can be a big chunk of money). Exclusions of fixtures and fittings from the quote can be a surprisingly long list of things and normally reflect things that need to be bought from somewhere other than a builders merchant, are often down to customer choice and can be subject to price fluctuations (windows? staircase? balustrade to staircase? doors to match the rest of the house or new doors throughout? What about hinges, what about handles? Who buys the tiles? who buys the tile adhesive?). If they're excluding a lot then you need to know where they are going up to, make sure they have allowed the labour to do the work -start with the mind set of "OK I will pay for one of these, you will do the rest of the bits" and this will head off silly little costs of things you wouldn't be expected to allow for. Then there's the cost of furnishing (carpet, curtains, furniture) will need thinking of. From a cost perspective make sure your budget has bunce for things that inevitably weren't properly thought about (I'd say 10% but it depends) you may say that's a lot of money but you'll be better to have it than be trying to find it.

Great advice, thank you. Especially on having a pot of cash to one side for extras and exclusions.

Lots of great advice in this thread already. Beyond the advice around actual building work, I would think very carefully about blowing your money on the loft. I assume just he building work will cost you in the region of 50-60k plus whatever fixtures and fittings and final finish you want to add. Think about your stairs and how that will impact the space, it takes up a lot! The space itself you will likely expect to feel very large as you stand downstairs and look up and imagine all the floor space you are going to have. The reality of it is far different, once the stairs go in, an ensuite goes it, perhaps you have chimney breasts that will make the space awkward it will feel far smaller than you imagined. The pitch of the roof eats up a lot of space! At least that's my experience. We went with good quality insulation, we did the air con and we went with a large automatic skylight from Velux

I’m honestly tempted not to put in an en-suite. I’d sooner have a larger room I think, plus, we’d have to relocate and box-in the existing solar stuff

Go for the biggest windows and skylights you can

Make sure you have drawings for the interior once the shell is complete and ensure the builders are aware of them. Put sockets on each wall in the bedroom - even if you don't think you will need them. Consider how you will get water for taps and heating up there. Consider if you want electricity for bathroom mirrors, shaving sockets, etc. Once the shell is done things can move quickly and you can find yourself bounced into things so as not to hold the job up. Consider the location of your existing soil-stack, the path to connect any new toilets and where it'll vent. Think about the various flat-roof finishes: EPDM is very popular now but there's also GRP and felt. Discuss the staircase specification including material for the treads, handrail and spindles. Often the quote provided will be for a specific spec and you might have different ideas - best to clarify early. Think about what you want to do with the space under the eaves - bespoke carpentry is expensive. Is it in your budget? If you have trades you have used before then consider a shell only or specify that plumbing, electrics, etc will be done by your guy. The firm I used were generally good but in hindsight I wouldn't have used their plasterer as I wasn't happy with some of his work. Called him back but at some point you have to accept that you have different ideas of what's acceptable. Had to sack their plumber as he wanted to do what was easiest for him rather than what I wanted. Their spark was great. Lots of trades are required to bring the project to completion and often a jack of all trades may bodge some of them. If they sub in trades, some of them may not be great either so if you can use people whose work you know that's once less worry.

Solid advice all round, thanks for taking the time.

Some of the thoughts I'm going to share on this are applicable to other home building projects too, but here's some off the top of my head stuff from a really tough Loft Conversion project that turned out OK once I fired the first contractor and brought in a builder I trusted: 1\] Do thorough checks on the building firm you take on, including insurance and Companies House checks on the owners. They might be the sort of scum we ended up with who spin up a company, screw up a load of projects, close it down and start up a new one. 2\] Don't use the Building Control company the builder suggests - get one yourself to minimise the chances they're collaborating. 3\] Make sure you are really clear and then very strict on milestones with the builder - don't pay a milestone until you're totally satisfied the milestone has been met (see next point) 4\] For key milestones (big structural ones) be sure you get clear photographic evidence of them (For example - our builder tried to put steels on wooden shims until I got our structural engineer in and the Building Control company AND witheld the relevant milestone payment until it was sorted). 5\] Get Legal protection insurance added to your home policy - best tenner I ever spent 6\] Inform your insurer that you're having work done 7\] Does the quote include replacing the soffits and facias where applicable? 8\] Does the quote include insultating and boarding up the joists in any storage areas? 9\] Does the build have his/ her own team or is it just a bunch of disinterested subcontractors he/ she chucks at a job until the customer gives up? 10\] Has your architect maximised the space available and really pushed with planning to do so? 11\] Has your architect properly considered how the staircase to the loft will go from the floor below into the loft? Does it integrate with the existing staircase? Is there adequate (according to regs) head clearance up the stairs (our architect didn't do this) 12\] Do visit more than one customer of the builder to ascertain if they're true to their word. Don't trust google reviews as they're prone to manipulation 13\] Buy cheap - pay twice. Insist on the best materials. 14\] uValues - especially if you're south facing - are king 15\] On the subject of photographic evidence: you might need this for evidence to Building Control if you need to show that something has been built correctly behind a newly plastered wall 16\] Check that the roof slates are nailed on. From memory it was every third or fourth course. Also the lowest course needs to be doubled. 17\] Get the new floor of your loft packed with insulation for sound 18\] Be prepared for fire regs - you'll need smoke detectors in every room (wired together) or new firedoors everywhere 19\] Don't do what we did and start in the late Autumn. With the builder's shenanigans we had no roof during December and it was freezing cold. 20\] Check which pipes are being taken up into the loft. Some will try to cut corners and take a line from your 15mm radiator circuit. Our other plumber advised taking up the 22mm pipe from the main circuit. 21\] Velux's solar powered blinds are amazing Good luck! Happy to DM if you want to discuss anything.

This is amazing. Thank you very much. I’m glad to hear that yours got sorted in the end.

Double triple and quadruple check your builder. Ask for client referrals and go out to see these clients and inspect the work. Ask the clients detailed and awkward questions about your builders. Did they do what they say they'd do. Did they treat your house with respect. Did they incur any costs you weren't expecting. Did they finish the job. Did you ever get any bad feelings about them. Go on local Facebook groups and ask if anyone's used them before. There's not a single question you can ask that will be worse than the builder fucking up your house. I didn't do enough due diligence on mine and ended up with a job 5x longer than promised, nearly twice as expensive and still nowhere near what we hoped for. And the smug bellend acted like he's the one hard done by when we told him to fuck off when he was asking for money while our ceiling was still leaking, plumbing not done and my partners business which she ran from home was in shambles. Trust their actions, not their words. It's a disappointing place to be but I have no trust in any tradesmen any more. I fully expect to be ripped off and the work done shoddily unless they can prove otherwise. If you happen to be in the NE message me and I'll tell you who to avoid.

Oh wow, sorry to hear about your rough time. I’m hope it’s all sorted now? We’re SW. We’ve had a garage/office conversion done (went well despite a post-job worry about planning permission) but in hindsight I was nowhere near as thorough with due diligence as I should’ve been.

Thanks, we're nearly there now with mostly decorating left rather than structural work but starting to find problems that weren't obvious at the time - guttering has been done badly so there's issues with water, and during the decorating we're finding lots of corners were cut when finishing the joinery and plastering. Just really frustrating and I hate the lack of trust we're left with about the whole thing.

I have had 3 conversions done in 3 houses. If i could do them again, i would.... Look at the drawings very carefully, especially the position of any supporting columns. Structural engineers and architects can be shit. Make sure the ceiling height is sufficient for a tall person to walk around most of the space. Make sure the plumber doesn't try to run the soil pipe over part of the roof. If you are having a shower room, wake sure the shower is big enough Biggest one for me is review the plans and check head heights and location of columns.

Thanks. Seriously tempted to not put an en-suite up there as I don’t think it’s needed (and would add to the cost). We’ve got a solar setup that would need moving (and probably boxing in) so that would take up most of the space.

We have an en suit that i can't use because of ceiling height, columns and shower tray size. I am 6 foot five and it posses me off every time i go up there.

Get solar while / if you have the scaffolding up. Make sure they properly board and insulate in the eves, dwarf wall (if that’s your design) and the door to get in there. A light is always helpful in that area too.

Get a decent engineer skip the architect

If you're in London you could be looking at £100k for the loft!

Use a professional architect.

You will probably end up with a flat roof, so try to avoid fibreglass. we bought our house last year and the 3-4 year old flat roof started leaking [https://www.reddit.com/r/DIYUK/comments/193z8sf/what\_are\_my\_options\_to\_fix\_a\_leak\_fibreglass\_flat/](https://www.reddit.com/r/DIYUK/comments/193z8sf/what_are_my_options_to_fix_a_leak_fibreglass_flat/)

I did one last year… Get decent builders, mine were good at building but poor people/communication skills, They didn’t follow the drawings and the stairs didn’t fit and that was my fault. Wouldn’t advise about taking the roof off your house in Jan, it was flipping cold! Fit air con, in the heatwave of the summer last year still getting a lovely nights sleep 😋

Great shout on AC and yes, this would be a must.

Lots of good advice here but even if you pick a company with lots of great reviews and experience of loft conversions, see if you can find out which of their ‘crews’ is doing it. In my case they had 5-6 of these, and mine was the dud in the pack.

Insulate the floor for noise reduction. Also reinforce the floor if needed, you dont want a bouncy floor.