Advice needed on fixing shed roof

One of the things we inherited when we moved into our new abode last month was a shed with a leaky roof.

Despite my appalling DIY skills, I'm giving it a go and attempting to replace the roof timbers and felt. I know there are some knowledgeable folk on here when it comes to DIY, so I'm hoping you can advise me on a couple of things.

I'm using tongue and groove timber for the replacement roof and I notice that the tongue and groove is cut slightly offset from the middle of the boards. So my question is, does it matter which way up I fit the boards? Does the thicker part of the board go at the top or the bottom?

Also, is it a good idea to use roofing felt adhesive, or will felt nails alone be sufficient?

All advice gratefully received.

 

Tongue and groove often has what is known as a "v" as well, a chamfer 45 degrees, this forms a v shape when the boards are put together, maybe that is why the tongue is off centre, if not then I dont have a clue.

I'd use felt adhesive if you can, clout nails always allow some moisture through and the adhesive helps in sealing it.

 

You could use T&G timber for a shed roof but its rather expensive.

The better way is to use 18mm OSB3 board and felt over that.

Not used felt as such, sure other would advise , though looks like plenty of advice on the web.
Roofing guide | Wickes.co.uk

One thing I have learnt over the years, if using any wood outdoors, treating it with a wood preservative first really does improve its life dramatically.

 

Unless it's an emergency, I avoid re-felting shed roofs in cold weather as I just can't get the same level of finish as when replacing in warm summer weather when it's softer and more workable.

Having said that, Black Friday is on 24th November when Wickes normally do 15 to 20% off promotion.

If using Sterling board in lieu of t&g boadin, the roof might benefit from some additional rafters, easier to fit when the boarding's off than retrospectively.

 

Thanks for all the advice everyone.

Should have checked on here before I started the job shouldn't I? I've already bought the t&g boards, easier to get in the back of the car for one thing. I have treated it with wood preservative, so at least I got that bit right.

We have three sheds here, another one looks as if it may need doing before too long and it's smaller than the one I'm doing at present, so I'll definitely consider OSB for that one.

Need to go out and get some adhesive this morning, wasn't sure whether I needed it or not.

 

As Scrungee said above , roof felting in cold weather can be difficult . The felt can crack when bending it around corners. There are two grades ( and prices ! ) of roofing felt . The 5 year stuff and the one below which has a 15 year guarantee. You pays your money and takes your choice.

IKO Green Ultra Durable Super Shed Felt 8 x 1m | Wickes.co.uk

 

Has anyone on here tried using EPDM (rubber) on their sheds rather than roofing felt? More expensive but lasts much longer, from what I have read. My roofing felt is OK at the moment but had wondered about EPDM when the time for replacement comes. Here's an ad picked at random:Firestone EPDM Shed Roof Kits

 

Going off my own experience, and how things are done here. Which may or may not be different to the UK.

The t&g's are offset because sometimes, they are fixed to whatever is under by "panel clips." These provide a hidden fastening. In this case, the "thinner" side will always be the underside. That because normally, the thick side will be the visible one, so the clips will only fit this way.

On a shed roof, it doesnt really matter, as the need for hidden fasteners is not there. They will either be nailed or screwed into place.

I personally would never use osb board in any form.

Regarding roofing felt. I've found that the best thing to use in this climate are self adhesive tiles made out of roofing felt. I'll try to take a photo of the ones I use when the weather allows.

 

EPDM looks very good , should last 20 years . The price is not to bad if you want a really long life roofing . The standard felt roof normally lasts 5 to 10 years.

 

Well, I got the job finished today (only took me 3 days ).

The t&g boards went on quite well, considering it's a 'custom made' shed of many years standing and none of the sides are true.

I got lucky with the weather too, it was quite a mild day here and I kept the roll of felt in the conservatory so it was fairly pliable and easy to work with.

One of the reasons the roof leaked was that it was 'bowed' with a dip in the middle, I think I've cured that by re positioning the some of the rafters, as they weren't all on the same level! The shed is a real 'home-made' job, the rafters being held in place by metal brackets screwed in to the sides of the shed, so it was just a question of unscrewing the brackets and getting the rafters in (approximately) the right position.

Hopefully, the shed now has a watertight roof - I'll see what happens next time it rains.

Anyway, thanks for the help folks. I'm so glad the job is done. I really, really, do not enjoy DIY so it's good to know there's always plenty of friendly advice available here on GC.

 

Corrugated roofing pannels are good, quite cheap too.