Shed build

[KevB]

Hi guys

Well I've had a few weeks off from building the shed, as I've been busy preparing for a new baby and decorating my daughters new bedroom

Hopefully tomorrow, weather permitting, I can make a start on boarding the roof.

I'm going to piece the roof in using 1200x1200 9mm cuts of osb, then another layer glued on top, staggering the joints. I don't think this is an ideal way to do the roof and originally I was going to use 25mm osb 8x4's (which I already have 5 sheets of). Then I realised that maybe the 4x2 rafters would not hold the weight of the sheets, which put me off. So now I will probably use them for the floor instead.

Anyways, not being sure what type of osb it is..do you guys think it will be ok with some water hitting it until next weekend? My dad is coming next weekend to do the torch on felt and whatever work I get done this weekend with the boarding will be covered with a tarpaulin, though it does (I think) let a little water/condensation in here and there.

What do you think guys, will it be ok?

 

[skipdiver]

First time i have glanced on this thread for a while and it looks very smart. I'm too late to answer your query regarding roof as you posted it last friday but regarding the polystyrene, up until a few years ago, we used it all the time, especially in floors. When i built caravans for a living many moons ago, we used to get through mountains of the stuff. 1" went in the British caravan walls and 2" in the ones we made for Sweden. It's not the best insulator out there but for free it's better than nowt.

 

[MickCheese]

Somehow I missed this thread so have just read through it in it's entirety.

Well done, looking good and I'm sure it will serve you well. I've put up several sheds for my wife to use as a workshop as we've moved houses. The sheds were purchased and I have fitted them out and insulated them. I spent more money on the fittings then you have on the whole build. It's always more difficult to re-use materials, I think you've done a really good job on that front.

Mick

 

[KevB]

Hi guys

Could you give me some quick advise please..

What it is.. My dad is coming tomorrow to help me lay the felt on the roof. He was meant to get me some underlay on the way home from work and forgot to get it. The problem is, he is only available tomorrow as he will be working away for 4 weeks.

Should I go ahead and lay the felt directly to the osb board? Has anyone done this before without any major problems over the long term?

The felt is the green mineral torch on type.

Any advise would really help from you more experienced shed/workshop builders..

 

[Woodchips2]

Hi Kev
Guidance here http://www.icopal.co.uk/~/media/IcopalU ... ochure.pdf. It isn't going to last as long with one less layer but I've just nailed mineral felt to a boarded roof in the past and it's lasted 7 or 8 years.
Regards Keith

 

[KevB]

Hi Kev
Guidance here http://www.icopal.co.uk/~/media/IcopalU ... ochure.pdf. It isn't going to last as long with one less layer but I've just nailed mineral felt to a boarded roof in the past and it's lasted 7 or 8 years.
Regards Keith

Hi mate

Thanks for that. If it lasted that long I'd be very pleased. Even 3-5 years I wouldn't mind. I've just read in that link you sent that it's no longer allowed - burning torch on felt directly to osb board, because of the obvious fire risk. This is something I've been a little worried about as well recently.

I may still go ahead, and just torch the thing straight on and hope for the best. Not the best practice but I don't claim to be any kind of professional lol :roll:

What would you do?

 

[cammy9r]

I dont think you should torch directly onto the osb as it sticks the felt to the entire sheet which will move and possibly tear the felt causing leaks. The bottom layer i believe is acting as a debonding or slip layer for the torch on felt.

 

[KevB]

Ok cheers for that mate. My dad couldn't make it this weekend and I didn't do any work on the roof. Although it is all boarded and covered. At least it gives me some extra time to get some underlay.

Some work on the floor today..

And more free pallet wood.. I'm going to end up with a wood yard for a back garden :roll:

Hopefully finish the floor and the roof next weekend

 

[KevB]

Hi guys

I've decided with the help of my brother in law, i'm going to have a go at torching on the felt myself. I have a few questions I was hoping you guys could help me out with..

Corners - How do I go about fixing the corners of the felt? Do I make any cuts in them, or is it just a matter of folding them into place?

Fascias - I understand that once the felt has been applied and folded around the edges of the roof, I then apply the sides and front fascia on top and sandwiching the felt. Is this correct? The back of the shed is different, the fascia sits underneath and back from the roof edge (by about 50mm). This is to allow water to drip directly into the gutter from the roof boards...is this correct regarding the back of the roof?

 

[blackrodd]

Many people are Nailing the base coat on, every 6-8" every which way and sticking the second sheet and cap sheet, I've had better results myself, since this came about, the end of condensation between the deck and felt and roof failure.
There's a bit of an art to torching the felt, so easy to catch on fire in just a few seconds.
When the roof deck on a mono pitch is fixed, and just before felting, the top edge and both sides should have a tilting fillet, basically just an Arris cut piece of 2"x2" nailed/screwed in place.
This keeps the water channeled down the the gutter end and stops water being blown in at the sides and rotting the fascia etc.
You need to make up "welts"for the outside edges.
Instead of me droning on, you'll probably be pleased to hear I've found some details of how to go about it.if you would like a butcher's.
You probably ought to read the whole thing.
HTH Regards Rodders
http://www.diydata.com/projects/flatroof/flatroof.php

 

[KevB]

Thanks for the advice and link blackrodd.

Do you think I can get away with the cap sheet straight onto the roof boards? I'm stressing a bit now and just want it done before it starts leaking. I definitely don't think I can afford a 3 layer system, though if there was some sort of cheap primer or something I could coat the boards with first, i'd do that?

Also, the arris cuts. I have some wood around about the same dimesnions, though it's not triangular shaped..you reckon I could use this and would the felt fold up against it ok?

Managed a little more work on the fascia/boxing in (whatever it is) around the back of the shed. I'm quite lost in this area without my dad, so just trying to do it as best I can and i'm hoping it will end up ok. I still need to cut the roof boards back, once I see how the gutter sits.

Lots of polystyrene left over from the floor, may use it for parts of the walls.

And a pic of the roof with the boards on.

 

[KevB]

Hi again guys

I'm really confused about this felt roof. There's so many products available, I don't know what I need..

I guess it's not a good idea to torch the cap sheet directly to the roof. Is there a flexible primer or something that will give me that movement under the cap sheet? Or something that I can use with the cap sheet to give me a two layer system?

It need to be something that is fairly cheap though as i'm not getting any overtime these days (hammer)

I spoke to my mate today and he said I could borrow his gas and torch, so that's all sorted. Just this underlay or primer to find now.

I think what is confusing me is, if I could do a two layer system.. do I buy nail on, glued on or torch on underlay?

 

[Paul200]

Hi again guys

I'm really confused about this felt roof. There's so many products available, I don't know what I need..

I guess it's not a good idea to torch the cap sheet directly to the roof. Is there a flexible primer or something that will give me that movement under the cap sheet? Or something that I can use with the cap sheet to give me a two layer system?

It need to be something that is fairly cheap though as i'm not getting any overtime these days (hammer)

I spoke to my mate today and he said I could borrow his gas and torch, so that's all sorted. Just this underlay or primer to find now.

I think what is confusing me is, if I could do a two layer system.. do I buy nail on, glued on or torch on underlay?

Can't help you with your roof Kev, not something I know much about and, like you say, the choice is bewildering, but I would have thought someone on here knew the answer :?: :wink: I'm still impressed with your progress mate. Take care.

 

[KevB]

Thanks Paul. My progress is slow at the best of times :roll: , though it's been very slow lately as I've had all sorts of other things going on. My priority at the moment is to get this roof sorted before the mrs drops this baby (any time now ) and before it starts leaking.

Though i'm sad that my dad isn't here to help me finish it, as it was our project together, I'm still enjoying it and it's a good learning curve for me. I really appreciate yours and other members interest in my thread on here. As i'm a bit of a loner when it comes to building my shed (which I quite like as I get to do everything exactly how I want it ha), it's nice to show people what i'm doing or trying to achieve

I was hoping that somebody could direct me to something I can put down on the osb boards before I torch the felt cap sheet on? Something that is fairly easy to lay and isn't too expensive..

Tomorrow I'm going to try and finish the feather edge, pieces of the fascias/boxing in that can be done before the felt and maybe the rest of the floor. Hopefully in the next coming weeks I can have all this done, including the roof. Then install the windows and hang the doors. After this I think i'll have to shut up shop and put the insulating and internal boarding on hold until the new baby grows a bit.

Will take some more pics tomorrow.

 

[KevB]

Blackrodd - Do you know when you mentioned the arris cuts. Would this be ok to fit this to the outside of the felt?

As you can see it's just two pieces of wood clamped together to show where it would be fixed. Acting as a fascia as well as a barrier to stop the water being blown into the fascia. The same along the front, though the fascia will be deeper here. The felt would be torched on and over the edges of the roof first, then the fascia/barrier fixed over the top. I'd then seal the inside edges where it meets the felt, to stop water getting in.

I think i'd find this way easier than trying to felt over the top of the barrier. What do you think?

 

[KevB]

Could anybody tell me whether I could nail any of these underlays down as part of a two layer system?

http://www.wickes.co.uk/IKO-Challenger-180-Sand-Underlay-20x1m/p/164182

http://www.wickes.co.uk/IKO-Trade-Medium-Duty-Sand-Surfaced-Underlay-20x1m/p/164175

I could really do with some advice on this as there's so many different products out there. I don't think it's good practice or a good idea for myself and my bro in law to torch directly onto osb boards. I've been looking for something that I can nail down, that has 20m on the roll and will allow me to torch on top of it?

This way I can nail the underlay myself, without bothering my bro in law at this stage

This is the capsheet I have..

 

[Roughcut]

On the Wickes website it does mention that this one can be nailed down:
http://www.wickes.co.uk/IKO-Trade-Mediu ... m/p/164175

 

[Bm101]

Hi Kev, in your links the descriptions have your answer I think.
First link:
Traditional pour & roll application
Second Link:
A sanded roofing felt, for use as an underlay to a multi layer system or as a single layer for shed/hutch roofs.
Sand finished on the top surface and slate finished on the underside
To be secured by nail fixing, cold adhesive or pour and roll hot bitumen

Don't forget when your torching you're heating the roll not the boards. They'll singe a little but easily take the heat. If you've not done it before, you're after getting the right amount of heat to get it to adhere well. Too little is as bad too much. I've only done it a couple of times so I'm certainly not giving advice! Just trying to help if you've not done it before.

Edit. beaten to it.

 

[KevB]

Thanks guys.

I did notice with the second link that it says it can be nailed down, though I wasn't too sure whether or not it would be compatible with the cap sheet I have..

If I nail the first layer down, does this mean that all of the strength and chances of the cap sheet ripping off is then down to the hold that the clout nails have in the underlayer, rather than the bitumen on the cap sheet? if that makes sense :roll:

I managed to finish the floor yesterday with a little help from my best mate..

Really happy with it as it's my first attempt at anything like this. Not the best of finishes for a floor, with it being osb, though it's 25mm thick and very strong. I had to cut in some pieces along the front and along past the door opening, which really should have been at the back of the shed, though I had already put the extra noggins in the wrong place under the floor long before I realised my mistake. Still happy though and glad that's another thing finished.

Building towers, then knocking them over

A good worker is a tidy worker..

 

[Bm101]

Looks good Kev. Passed the qualityinspection by the assessor too by the looks of things.