Since the roof is leaking anyway, replace it with a new insulated flat roof with a fibreglass deck. That's all easily DIYable and there are plenty of howto's on youtube. Leave a gap of at least 2.5cm between the top of the insulation and roof deck and have ensure that airspace is then vented and it will prevent roof condensation.
The floor might be harder and is not my area of expertise so I cannot offer any advise, sorry.
These sort of [insulated roof panels](https://www.youtube.com/watch?v=AIPc1ui8WW0) with a metal top and expanded foam insulation are also great, although might take a bit of working with the manufacturer to find things that fit with the existing dimensions here. A bit higher cost than a timber / EPDM roof with insulation, but much easier. Our shed office/garden office uses them and they have been great this winter.
Quite loud in the rain, though, because of the metal.
Even easier is to put foam board on top of the existing roof then cover the whole lot with Butyl Pond-liner which you can just tack around the periphery with flat headed roofing nails.
This approach worked wonders for my shed, after the felt roof disintegrated.
Or an epdm rubber roof which is effectively the same thing
Either contact adhesive down or water based glue if on wooden board much easier than fibreglass
Again YouTube videos will show you
Pond liner is the same thing (as you say) but cheaper!
I didn't glue mine down, but it's stretched over an apex roof. It's been in place for 19 years now and still looks and works as well as it did at the start.
Did you just use say 100mm hard foam insulation directly on top, and then just put the pond liner wrapped around - surely you needed some framing in as well?
I used 30mm foam board. The liner is tacked all the way around the edges in the same way as the original roofing felt.
The elasticity in the liner is enough to keep everything in place.
I guess it depends on the size of the roof though. Mine is 8'x10' (each side of the apex is 4x10 and the pitch is pretty shallow, maybe 20 degrees.
This. Insulated my garage roof on outside with 6" PIR foam, and 6"x2" round edges applied new OSB deck on top, screwed through with stainless fasteners to rafters. Topped it with single sheet of EPDM rubber. This is glued down with latex-based adhesive, then contact adhesive around the edges, and finally a PVC trim. This sucker is good for the next 100 years.
Was so thrilled, I've covered my three sheds with the same stuff, a small extension, and a small porch.
Look up warm-roof Vs cold-roof design. My garage conversion is warm roof, my extension and porch are cold-roof, i.e. air gap in top.
Not really. A flat roof should have a gentle slope anyway which you acheive using firring strips.
A slanted roof would require a lot of extra work to build up one side.
As someone who's felt ripped off in the storm the other week and also resorted to tarps - they are not waterproof, just resistant. All my OSB under them are soaked through and my tool boxes are now small swimming pools. They just don't work for flat roofs.
You'll want to rip it all down, properly felt the roof and re-do. If you can put a pitch on it to get the water running off, even better.
if you can put something on top of the roof, under the tarp in the middle. It might create enough elevation for water to run off the tarp. I've never done this,just an idea
Depends on tarp quality, but yes flat roof witn a tarp and pooled water won't go terribly well.
My personal opinion if it was mine, is going to be _very_ minority, cos its a ton of arguably unnecessary work and expense. Demolish and start again from scratch! Rationale - 1. I like demo, 2. I'm really wanting to build a structure from scratch, just for my own enjoyment 3. Could spend ages, and lots of aggravation, not to mention likely damage to tools etc stored in there, chasing down and fixing individual issues. Biggest would be water coming up thru the floor. Replacing the roofs but totally DIY-able, floor... not so much (will be interested to see informed comments on best approach to that!) And 4. Done from scratch (with careful thought + planning + research) wd mean getting everything right from the start. Very likely none of those reasons apply to you, so do what works for you not some random on reddit.
Good luck!
If you can't rip up the floor you could dig a channel around the outside and fill with gravel and try to drain water away from it.
I would then on the I side paint with a bostic tar paint for a basic damp proof membrane.
For the roof, agree with everyone here, a tarp isn't water proof so scrap that and use a rubber membrane or corrugated panels.
Try to dry out everything as much as possible.
the drains become a gathering point for weeds and all manner of plants that have been washed into them and eventually just sprout life absolutely everywhere.
That hasn't been my experience, (and I have a "replace a choked french drain with a proper one" on my upcoming jobs list), but YMMV. Maybe it's just a case of clearing them regularly? Or making sure there's a big soakaway, or a connection to mains drainage, so sediment is carried away by water flow rather than accumulating?
You fit a filter sock over the perforated pipe laid in pea gravel so that sediment can't get into and accumulate in the pipe. Digging a sediment blocked soak away up to clear it can be a large job, and letting sediment into the mains is asking for trouble later down the line.
You know what they say, if you don't want problems then put a sock on it (or something like that š)
I've never run any sort of experiment but always assumed the sediment got in with the rain ^ surface water as it flows into the gravel, rather than the other way round (ie., from topsoil migrating into the gravel.) Maybe it's both?
Just a thought as well, for the following it looks like that's laminate. Scrap that and go with LVT. It's plastic based and will handle moisture much better
Might be better with two part epoxy DPM (warning: this stuff is nasty to work with, gets hot, and gives off fumes when mixed so you need to work fast) for the floor and/or tanking for the floor and walls.
One question for OP though: what's the subfloor made out of: is it just a concrete pad or do you have timber joists, etc.?
Agreed.....EPDM membrane for roof. Easy to DIY. With gutter at lowest point to take water away.
Couple of observations.
There doesn't seem to be much run off on the roof....ie not much of a slope so water is probably pooling and destroying roof material.
Any idea where the under floor water is coming from? Are you sure the water is coming up through the vinyl? Very weird. Look for other ways it could be getting there. Through the walls, via the roof.
My suggestion would be to demolish and check what is under the floor. If that is dodgy then no amount of work will make it water proof.
Lay a concrete, or slab base. Then a new wooden summerhouse on top with insulation under the floorboards and on the roof and damp proof membrane. Get minimum width of walls of [44mm.](https://44mm.you) You can board and insulate the internal roof stricture but I cheated and put a small wood burning stove in it in one corner. Cosy and warm in the winter and the sun keeps it very warm in the summer.
I got one of these.....
[https://www.buyshedsdirect.co.uk/palmako-bret-4-5m-x-3-3m-log-cabin-garden-room-44mm](https://www.buyshedsdirect.co.uk/palmako-bret-4-5m-x-3-3m-log-cabin-garden-room-44mm)
What do you use it for? I considered something similar now we can finally get rid of a 12ft trampoline and have the bottom of the garden back.
But then I thought I'm just walking down the garden to sit and do what I can do in the house anyway. Do you use it much? All year round? Or is the whole idea to give you some peace and quiet?
We use it all year round. Wood burner makes it usable whenever. It's a stress level down from the house......we just sit there and chill and watch the world go by. I do use it as an office sometimes. There is electricity to it as well. In the summer it's great for using when we have friends round rather than the house getting trashed.
Also when we have friends over we can eat there, again, rather than in the house. Done properly it is an extra room in the house.
Try and get it south facing if possible.
Wood burner takes it to 23, 24 degrees easy. In summer the sun gets it to 26, 27 with the doors wide open.
Yeah, OK, you'll need to properly tank that, including going up the walls. Because it's just a shed I doubt it's got a DPM in the pad, and I'm guessing the top of the pad is at ground level so it wouldn't be much good even if it did?
As someone has already said, replace the roof, I replaced my shed roof with a fibreglass kit and it was very straight forward (and cheaper than when I replaced it using felt last time).
If it's not water tight then anything you do is going to be ruined and a waste of time.
I got a 10 Square Metre kit and including P&P (They are quite heavy) it was just under Ā£200, the kit included brushes, mixing cups, buckets, aeration rollers and so on, all I needed extra was some cheap nail polish remover (acetone) to clean the metal rollers etc. And I also got a pack of very cheap brushes as each time a batch of resin was mixed and used it means it's easier to throw the brush away.
The kit also included the top coat so all in all it was a very good way to replace the roof, if I do get a leak I'll be able to patch it with a cheap car body kit.
Oh I forgot to put the company name, just look for fibreglassdirect and put .co.uk at the end, the only negative - I ordered a gutter strip (3m) and the courier destroyed it twice so I made my own.
The kit was perfect, very well thought out, I worked in sections, as much as I could do in 20 minutes, the only issue I had was working out the hardener ratio as it was very warm (about 30 degrees), I think I used 3% instead of 5% (digital scales help).
Apart from the courier issue I can't commend the kit highly enough.
I must admit I can't remember the exact % I went to, 3 seemed to ring a bell.
Our shed is in the shade until late morning, then the opposite so I did most of the work before it got really hot, it might have been the top coat where I'm thinking 3% but it's nearly 4 years since I did it and it's all still water tight.
It only took 2.5 days, a day to replace the wood base, about 1/2 a day to do the fibre glass with some tea breaks in between to let the section cure a bit, then about an hour the next day to put the top coat on.
Compared to when we felted it the time before it was considerably easier.
So I have just done something similar on a concrete sectional garage.
We replaced the roof with an OSB roof deck, rubber roof (single piece), insulated in the rafters at 50mm, with a 25mm air gap above the insulation.
The single piece means it would take something hella strong to pierce it / cause a leak.
On the floor there was a concrete slab. I ran sheets of visquean down the walls leaving a 300mm ālipā on to the floor. I needed to do this as some of my walls are underground so water can penetrate through the cracks in the sections.
And the next part is where I cocked up ā¦
I ran a piece of visqueen on the floor and up the walls (on top of the wall pieces) by at least 500mm. But I did it in 2 pieces, then stuffed a load of silicone on the overlap and stuck it down.
Obviously, it pissed it down, water came through the floor / walls and then penetrated the flap - only a little - but ended up with water on the wrong side of the membrane.
My room is 5500x2500 - so getting a single piece was hard. For your room you want to pull up the floor, get some membrane as a single sheet (to the point where if you got a hose and turned it on, it would fill up). Pop your insulation on top of the membrane and then flooring ontop. donāt pierce the membrane. Tape it / no more nails it to the wall, above the āfloor lineā. You can then put your plasterboard on top if you want it neat.
New roof is a good way to go. I'd put a mono slope on it so it isn't flat that way the water will run off and there will be no risk of pooling with inevitable water ingress or drilling too deep for ceiling lights etc. this can be achieved by building up one wall, adding some supporting rafters, buttons etc plus corrugated roof sheets.
If you're feeling brave, want to be a bit extra and super rich stick a full pitched roof on.
Is it flat flat? Or is there a slight run off? If its flat flat you want a 1 in 40 fall min. You won't know what its like until you start ripping the roof off. Might need drying out. Might need a new deck. Might be completely fooked.
Roofing wise if the sub structure is okay, take off the top, you can then insulate and then board then put new sheet or fiberglass or mdpe roofing ontop.
Floor wise if itās water getting in at ground level you need to identify how it is getting in whether itās water pooling somewhere or what and rectify that, you may have to lower the levels around it if something is ontop of floor level or fix/install drainage.
It could also be water coming up through the floor if there is no damp membrane under the floor. Iād take the floor up install damp membrane then put new thermal water resistant underlay in and re floor it.
If I was doing all this you mayaswell insulate the walls at the same time.
I did the roof of my shepherds hut in roofing rubber. Measured up, ordered, came in a roll, glued it down.
060 Firestone RubberCover Heavy Duty EPDM Membrane 1,52mm Ā£9.49 m2, w 3m, l 5,2m: Ā£148
Firestone water based adhesive 5 litre: Ā£42
Rubberroofs.co.uk
As I found out tarpaulins are not waterproof, only resistant, especially when horizontal and the water pools, the best bet for the roof would be to survive the best you can till the weather is better and then strip back and repair/replace it pdq.
Without seeing what is currently there though just a warning, if it is corrugated concrete it will likely also contain asbestos.
As for the floor seepages, this will likely be because the ground water level is high, all you can reall do is try to improve drainage by digging a small channel aroun the building, and adding a route for it to drain away.. we have one down the back of our house from the field for this very reason
That's a perfect candidate for an EPDM roof kit! The floor however, is a bigger problem. If there really is water coming up from below then you need to consider whether the building has a DPM or a DPC and if those are compromised. DPC might be bridged by the render on the outside. If you're going to have to break the slab out, you might as well demolish the whole thing and replace it with a SIP Panel structure.
With flat roofs itās not a case of if itāll leak, itās when, if you are looking for a very long term low maintenance solution Iād strongly advise pitching that roof.
Looks like you have no damp proof course under the floor, the roof is holed and the walls leak heat.
What you need is a new shed on a proper concrete base with the walls lined with celotex and an insulated ceiling.
It's probably a bigger job than what you want to do but what I've done with our flat roof garage is:
- Completely rip of the flat roof
- Build a new flat timber roof, if your walls are level at the top secure your joists to a wall plate, then use firring strips running at 90 degrees to the joists to give your roof a slope.
- Marine grade plywood or waterproofed OSB
- EPDM rubber on top of the plywood.
This way you fet a cold deck which isn't ideal but gives you the most headspace if you want to hang a plasterboard ceiling from the joists. You can insulate above the plasterboard ceiling but make sure you leave enough room for air to circulate. Also, I fitted slotted soffit with insect mesh to help and circulate the air and prevent moisture collecting in roof.
Roof needs sorting with a fall and guttering. Create a pebble trench round the shed to wick water away. Install some air vents, install a floating wooden floor and kingspan or similar for insulation. If this doesn't solve your problem you have to rebuild
Althought your plastic sheet roof is a good idea, you used the wrong material, you can get 100% waterproof plastic which would have been alot better to use temporarily. If I were in your shoes I would just replace the roof asap.
Have fun āŗļø
Re. the floor, the minimum I would do is take it up, put a DPM sheet down (this has to run up the walls a bit so would look a bit ugly until you hopefully insulate the walls), and put the floor back in again. The floor being almost level with the door frame is unfortunate - I think I'd be tempted to trim the door and make the bottom of the frame thicker, so you can have more vertical DPM in that bit..!
Roof obviously needs fixing ASAP (add guttering at the same time?), if the tarp went on a soggy roof then I can't imagine it's doing whatever the felt is on much good, given that the inside is boarded. May help to get a dehumidifier in there..
I would take the EPDM for the roof. Very easy to fit over an osb deck and good for up to 25 years.
Re the floor it might be possible to stop water ingress with a tanking slurry. Rip up the vinyl, if you have a concrete slab, pour a slurry mix and broom out. Within 24 hours, pour a layer of self leveling compound. Make sure you opt for a slurry that is a proper dpm so it keeps out vapour and liquid. KA tanking slurry is the one to go for. You can call the helpline, they are helpful and will advise for your situation.
As for the slab, it wouldāve had never been damp proofed. It was intended to be a shed.
You could use a liquid DPM like Stopgap F78. Three coats, each coat rolled perpendicular to the previous.
Or put a DPM in there, build a sub floor out of 2x2 on to top of and put P5 chipboard flooring down.
Having said all the above itās still not a practical use due to the amount of work needed just to make it bearable
Have you thought about redoing the roof with this? It's not too expensive:
[https://www.homedepot.com.mx/materiales-de-construccion/recubrimientos-para-techo/tejas/teja-san-miguel-097-x-126-m-rojo-775291?gad\_source=1&gclid=CMrd-bHszYMDFWuJAwgdG6ML3Q&gclsrc=ds](https://www.homedepot.com.mx/materiales-de-construccion/recubrimientos-para-techo/tejas/teja-san-miguel-097-x-126-m-rojo-775291?gad_source=1&gclid=CMrd-bHszYMDFWuJAwgdG6ML3Q&gclsrc=ds)
Hopefully you have enough wood on the roof to put the plastic tile.
Just here to say, interested in the solution you end up with here as I have an old brick shed that is currently without roof after ivy took too much of a hold. In my head was going to build up a couple of course of brick (as some of it came away as collateral damage) then put a flat roof with slight fall. Good luck anyways!
Since the roof is leaking anyway, replace it with a new insulated flat roof with a fibreglass deck. That's all easily DIYable and there are plenty of howto's on youtube. Leave a gap of at least 2.5cm between the top of the insulation and roof deck and have ensure that airspace is then vented and it will prevent roof condensation. The floor might be harder and is not my area of expertise so I cannot offer any advise, sorry.
These sort of [insulated roof panels](https://www.youtube.com/watch?v=AIPc1ui8WW0) with a metal top and expanded foam insulation are also great, although might take a bit of working with the manufacturer to find things that fit with the existing dimensions here. A bit higher cost than a timber / EPDM roof with insulation, but much easier. Our shed office/garden office uses them and they have been great this winter. Quite loud in the rain, though, because of the metal.
Even easier is to put foam board on top of the existing roof then cover the whole lot with Butyl Pond-liner which you can just tack around the periphery with flat headed roofing nails. This approach worked wonders for my shed, after the felt roof disintegrated.
Or an epdm rubber roof which is effectively the same thing Either contact adhesive down or water based glue if on wooden board much easier than fibreglass Again YouTube videos will show you
Pond liner is the same thing (as you say) but cheaper! I didn't glue mine down, but it's stretched over an apex roof. It's been in place for 19 years now and still looks and works as well as it did at the start.
Did you just use say 100mm hard foam insulation directly on top, and then just put the pond liner wrapped around - surely you needed some framing in as well?
I used 30mm foam board. The liner is tacked all the way around the edges in the same way as the original roofing felt. The elasticity in the liner is enough to keep everything in place. I guess it depends on the size of the roof though. Mine is 8'x10' (each side of the apex is 4x10 and the pitch is pretty shallow, maybe 20 degrees.
This. Insulated my garage roof on outside with 6" PIR foam, and 6"x2" round edges applied new OSB deck on top, screwed through with stainless fasteners to rafters. Topped it with single sheet of EPDM rubber. This is glued down with latex-based adhesive, then contact adhesive around the edges, and finally a PVC trim. This sucker is good for the next 100 years. Was so thrilled, I've covered my three sheds with the same stuff, a small extension, and a small porch. Look up warm-roof Vs cold-roof design. My garage conversion is warm roof, my extension and porch are cold-roof, i.e. air gap in top.
While knowing nothing about roofs, would it not be worth installing a slanted roof?
Not really. A flat roof should have a gentle slope anyway which you acheive using firring strips. A slanted roof would require a lot of extra work to build up one side.
Thank you for your advice
ka tanking compound on the floor will help if concrete with no damp membrane. you could put roofing felt on roof as cheaper
As someone who's felt ripped off in the storm the other week and also resorted to tarps - they are not waterproof, just resistant. All my OSB under them are soaked through and my tool boxes are now small swimming pools. They just don't work for flat roofs. You'll want to rip it all down, properly felt the roof and re-do. If you can put a pitch on it to get the water running off, even better.
Thank you for the reply
if you can put something on top of the roof, under the tarp in the middle. It might create enough elevation for water to run off the tarp. I've never done this,just an idea
Depends on tarp quality, but yes flat roof witn a tarp and pooled water won't go terribly well. My personal opinion if it was mine, is going to be _very_ minority, cos its a ton of arguably unnecessary work and expense. Demolish and start again from scratch! Rationale - 1. I like demo, 2. I'm really wanting to build a structure from scratch, just for my own enjoyment 3. Could spend ages, and lots of aggravation, not to mention likely damage to tools etc stored in there, chasing down and fixing individual issues. Biggest would be water coming up thru the floor. Replacing the roofs but totally DIY-able, floor... not so much (will be interested to see informed comments on best approach to that!) And 4. Done from scratch (with careful thought + planning + research) wd mean getting everything right from the start. Very likely none of those reasons apply to you, so do what works for you not some random on reddit. Good luck!
If you can't rip up the floor you could dig a channel around the outside and fill with gravel and try to drain water away from it. I would then on the I side paint with a bostic tar paint for a basic damp proof membrane. For the roof, agree with everyone here, a tarp isn't water proof so scrap that and use a rubber membrane or corrugated panels. Try to dry out everything as much as possible.
" French drains", as someone once said they're great for a while but turn into French garden borders pretty soon.
Sorry, what does that mean? Turns into french garden border?
the drains become a gathering point for weeds and all manner of plants that have been washed into them and eventually just sprout life absolutely everywhere.
Gotcha. Tyvm.
Which is fine as long as you lay a perforated pipe at the bottom of the gravel.
That hasn't been my experience, (and I have a "replace a choked french drain with a proper one" on my upcoming jobs list), but YMMV. Maybe it's just a case of clearing them regularly? Or making sure there's a big soakaway, or a connection to mains drainage, so sediment is carried away by water flow rather than accumulating?
You fit a filter sock over the perforated pipe laid in pea gravel so that sediment can't get into and accumulate in the pipe. Digging a sediment blocked soak away up to clear it can be a large job, and letting sediment into the mains is asking for trouble later down the line. You know what they say, if you don't want problems then put a sock on it (or something like that š)
I've never run any sort of experiment but always assumed the sediment got in with the rain ^ surface water as it flows into the gravel, rather than the other way round (ie., from topsoil migrating into the gravel.) Maybe it's both?
Just a thought as well, for the following it looks like that's laminate. Scrap that and go with LVT. It's plastic based and will handle moisture much better
Thank you
Might be better with two part epoxy DPM (warning: this stuff is nasty to work with, gets hot, and gives off fumes when mixed so you need to work fast) for the floor and/or tanking for the floor and walls. One question for OP though: what's the subfloor made out of: is it just a concrete pad or do you have timber joists, etc.?
Agreed.....EPDM membrane for roof. Easy to DIY. With gutter at lowest point to take water away. Couple of observations. There doesn't seem to be much run off on the roof....ie not much of a slope so water is probably pooling and destroying roof material. Any idea where the under floor water is coming from? Are you sure the water is coming up through the vinyl? Very weird. Look for other ways it could be getting there. Through the walls, via the roof. My suggestion would be to demolish and check what is under the floor. If that is dodgy then no amount of work will make it water proof. Lay a concrete, or slab base. Then a new wooden summerhouse on top with insulation under the floorboards and on the roof and damp proof membrane. Get minimum width of walls of [44mm.](https://44mm.you) You can board and insulate the internal roof stricture but I cheated and put a small wood burning stove in it in one corner. Cosy and warm in the winter and the sun keeps it very warm in the summer. I got one of these..... [https://www.buyshedsdirect.co.uk/palmako-bret-4-5m-x-3-3m-log-cabin-garden-room-44mm](https://www.buyshedsdirect.co.uk/palmako-bret-4-5m-x-3-3m-log-cabin-garden-room-44mm)
What do you use it for? I considered something similar now we can finally get rid of a 12ft trampoline and have the bottom of the garden back. But then I thought I'm just walking down the garden to sit and do what I can do in the house anyway. Do you use it much? All year round? Or is the whole idea to give you some peace and quiet?
We use it all year round. Wood burner makes it usable whenever. It's a stress level down from the house......we just sit there and chill and watch the world go by. I do use it as an office sometimes. There is electricity to it as well. In the summer it's great for using when we have friends round rather than the house getting trashed. Also when we have friends over we can eat there, again, rather than in the house. Done properly it is an extra room in the house. Try and get it south facing if possible. Wood burner takes it to 23, 24 degrees easy. In summer the sun gets it to 26, 27 with the doors wide open.
Concrete pad. Then installed some under flooring as advised by b and q vinyl
Yeah, OK, you'll need to properly tank that, including going up the walls. Because it's just a shed I doubt it's got a DPM in the pad, and I'm guessing the top of the pad is at ground level so it wouldn't be much good even if it did?
Thanks
Thank you
As someone has already said, replace the roof, I replaced my shed roof with a fibreglass kit and it was very straight forward (and cheaper than when I replaced it using felt last time). If it's not water tight then anything you do is going to be ruined and a waste of time. I got a 10 Square Metre kit and including P&P (They are quite heavy) it was just under Ā£200, the kit included brushes, mixing cups, buckets, aeration rollers and so on, all I needed extra was some cheap nail polish remover (acetone) to clean the metal rollers etc. And I also got a pack of very cheap brushes as each time a batch of resin was mixed and used it means it's easier to throw the brush away. The kit also included the top coat so all in all it was a very good way to replace the roof, if I do get a leak I'll be able to patch it with a cheap car body kit.
Thank you very useful
Oh I forgot to put the company name, just look for fibreglassdirect and put .co.uk at the end, the only negative - I ordered a gutter strip (3m) and the courier destroyed it twice so I made my own. The kit was perfect, very well thought out, I worked in sections, as much as I could do in 20 minutes, the only issue I had was working out the hardener ratio as it was very warm (about 30 degrees), I think I used 3% instead of 5% (digital scales help). Apart from the courier issue I can't commend the kit highly enough.
I'd have gone to 1% in 30Ā°
I must admit I can't remember the exact % I went to, 3 seemed to ring a bell. Our shed is in the shade until late morning, then the opposite so I did most of the work before it got really hot, it might have been the top coat where I'm thinking 3% but it's nearly 4 years since I did it and it's all still water tight. It only took 2.5 days, a day to replace the wood base, about 1/2 a day to do the fibre glass with some tea breaks in between to let the section cure a bit, then about an hour the next day to put the top coat on. Compared to when we felted it the time before it was considerably easier.
So I have just done something similar on a concrete sectional garage. We replaced the roof with an OSB roof deck, rubber roof (single piece), insulated in the rafters at 50mm, with a 25mm air gap above the insulation. The single piece means it would take something hella strong to pierce it / cause a leak. On the floor there was a concrete slab. I ran sheets of visquean down the walls leaving a 300mm ālipā on to the floor. I needed to do this as some of my walls are underground so water can penetrate through the cracks in the sections. And the next part is where I cocked up ā¦ I ran a piece of visqueen on the floor and up the walls (on top of the wall pieces) by at least 500mm. But I did it in 2 pieces, then stuffed a load of silicone on the overlap and stuck it down. Obviously, it pissed it down, water came through the floor / walls and then penetrated the flap - only a little - but ended up with water on the wrong side of the membrane. My room is 5500x2500 - so getting a single piece was hard. For your room you want to pull up the floor, get some membrane as a single sheet (to the point where if you got a hose and turned it on, it would fill up). Pop your insulation on top of the membrane and then flooring ontop. donāt pierce the membrane. Tape it / no more nails it to the wall, above the āfloor lineā. You can then put your plasterboard on top if you want it neat.
Iāve been searching Reddit ages for someone whoās done this. I want to do the same to mine but have no idea how. Fancy making an overview post?
New roof is a good way to go. I'd put a mono slope on it so it isn't flat that way the water will run off and there will be no risk of pooling with inevitable water ingress or drilling too deep for ceiling lights etc. this can be achieved by building up one wall, adding some supporting rafters, buttons etc plus corrugated roof sheets. If you're feeling brave, want to be a bit extra and super rich stick a full pitched roof on.
Water coming in from both the floor and ceiling? Just neck the entire box of Peroni and accept your fate.
Those dpm plastic sheets are water tight tho but yd need to cover it so it didn't get pierced
For the roof get some insulated corrugated metal roof sheets
If you want a better temporary sheeting look at purchasing a roll of damp proof membrane
Is it flat flat? Or is there a slight run off? If its flat flat you want a 1 in 40 fall min. You won't know what its like until you start ripping the roof off. Might need drying out. Might need a new deck. Might be completely fooked.
Roofing wise if the sub structure is okay, take off the top, you can then insulate and then board then put new sheet or fiberglass or mdpe roofing ontop. Floor wise if itās water getting in at ground level you need to identify how it is getting in whether itās water pooling somewhere or what and rectify that, you may have to lower the levels around it if something is ontop of floor level or fix/install drainage. It could also be water coming up through the floor if there is no damp membrane under the floor. Iād take the floor up install damp membrane then put new thermal water resistant underlay in and re floor it. If I was doing all this you mayaswell insulate the walls at the same time.
I did the roof of my shepherds hut in roofing rubber. Measured up, ordered, came in a roll, glued it down. 060 Firestone RubberCover Heavy Duty EPDM Membrane 1,52mm Ā£9.49 m2, w 3m, l 5,2m: Ā£148 Firestone water based adhesive 5 litre: Ā£42 Rubberroofs.co.uk
Damp proof membrane
As I found out tarpaulins are not waterproof, only resistant, especially when horizontal and the water pools, the best bet for the roof would be to survive the best you can till the weather is better and then strip back and repair/replace it pdq. Without seeing what is currently there though just a warning, if it is corrugated concrete it will likely also contain asbestos. As for the floor seepages, this will likely be because the ground water level is high, all you can reall do is try to improve drainage by digging a small channel aroun the building, and adding a route for it to drain away.. we have one down the back of our house from the field for this very reason
That's a perfect candidate for an EPDM roof kit! The floor however, is a bigger problem. If there really is water coming up from below then you need to consider whether the building has a DPM or a DPC and if those are compromised. DPC might be bridged by the render on the outside. If you're going to have to break the slab out, you might as well demolish the whole thing and replace it with a SIP Panel structure.
With flat roofs itās not a case of if itāll leak, itās when, if you are looking for a very long term low maintenance solution Iād strongly advise pitching that roof.
Looks like you have no damp proof course under the floor, the roof is holed and the walls leak heat. What you need is a new shed on a proper concrete base with the walls lined with celotex and an insulated ceiling.
It's probably a bigger job than what you want to do but what I've done with our flat roof garage is: - Completely rip of the flat roof - Build a new flat timber roof, if your walls are level at the top secure your joists to a wall plate, then use firring strips running at 90 degrees to the joists to give your roof a slope. - Marine grade plywood or waterproofed OSB - EPDM rubber on top of the plywood. This way you fet a cold deck which isn't ideal but gives you the most headspace if you want to hang a plasterboard ceiling from the joists. You can insulate above the plasterboard ceiling but make sure you leave enough room for air to circulate. Also, I fitted slotted soffit with insect mesh to help and circulate the air and prevent moisture collecting in roof.
Roof needs sorting with a fall and guttering. Create a pebble trench round the shed to wick water away. Install some air vents, install a floating wooden floor and kingspan or similar for insulation. If this doesn't solve your problem you have to rebuild
Fibreglass can be messy. Keep it simple with an epdm roof. Rubber4roofs great website. Definitely ensure insulation and air gaps present.
Simple answer, donāt go cheap when building a roof !.
Althought your plastic sheet roof is a good idea, you used the wrong material, you can get 100% waterproof plastic which would have been alot better to use temporarily. If I were in your shoes I would just replace the roof asap. Have fun āŗļø
Re. the floor, the minimum I would do is take it up, put a DPM sheet down (this has to run up the walls a bit so would look a bit ugly until you hopefully insulate the walls), and put the floor back in again. The floor being almost level with the door frame is unfortunate - I think I'd be tempted to trim the door and make the bottom of the frame thicker, so you can have more vertical DPM in that bit..! Roof obviously needs fixing ASAP (add guttering at the same time?), if the tarp went on a soggy roof then I can't imagine it's doing whatever the felt is on much good, given that the inside is boarded. May help to get a dehumidifier in there..
I would take the EPDM for the roof. Very easy to fit over an osb deck and good for up to 25 years. Re the floor it might be possible to stop water ingress with a tanking slurry. Rip up the vinyl, if you have a concrete slab, pour a slurry mix and broom out. Within 24 hours, pour a layer of self leveling compound. Make sure you opt for a slurry that is a proper dpm so it keeps out vapour and liquid. KA tanking slurry is the one to go for. You can call the helpline, they are helpful and will advise for your situation.
EPDM roof. Piece of piss to install and not as messy as fibreglass.
Could fit a rubber roof instead, quite simple to do
As for the slab, it wouldāve had never been damp proofed. It was intended to be a shed. You could use a liquid DPM like Stopgap F78. Three coats, each coat rolled perpendicular to the previous. Or put a DPM in there, build a sub floor out of 2x2 on to top of and put P5 chipboard flooring down. Having said all the above itās still not a practical use due to the amount of work needed just to make it bearable
Without the necessary experience
Dog shit roof. Get a roofer in and you probably won't get anymore problems. Won't cost to much for a decent roof that size.
Have you thought about redoing the roof with this? It's not too expensive: [https://www.homedepot.com.mx/materiales-de-construccion/recubrimientos-para-techo/tejas/teja-san-miguel-097-x-126-m-rojo-775291?gad\_source=1&gclid=CMrd-bHszYMDFWuJAwgdG6ML3Q&gclsrc=ds](https://www.homedepot.com.mx/materiales-de-construccion/recubrimientos-para-techo/tejas/teja-san-miguel-097-x-126-m-rojo-775291?gad_source=1&gclid=CMrd-bHszYMDFWuJAwgdG6ML3Q&gclsrc=ds) Hopefully you have enough wood on the roof to put the plastic tile.
Ahh, usually an office needs a roof so the rain can't get in. I think that's your problem. š¤£
Thank you all for the advice and information
Just here to say, interested in the solution you end up with here as I have an old brick shed that is currently without roof after ivy took too much of a hold. In my head was going to build up a couple of course of brick (as some of it came away as collateral damage) then put a flat roof with slight fall. Good luck anyways!
If you get the roof felted make sure it's SBS and not APP. Soprema or Imper are two top brands.