Building a Garden Office Advice Required
- Thread starter Markymark
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Boss
I know this is a bit after the event but. I ordered a quantity of 8'x4' OSB3 Sheets for the roof. Then someone asked me if they were T&G and I said no. This got me wondering if I should have used T&G boards assuming you can buy them at that size. Do I need to seal in any way the joints on the roof?
Also I need to install a metal drip edge at the eaves and at the rake edges. I am not sure what product I should use to create a drip edge or do Builders supplies offer a proprietary one?
Mark
I know this is a bit after the event but. I ordered a quantity of 8'x4' OSB3 Sheets for the roof. Then someone asked me if they were T&G and I said no. This got me wondering if I should have used T&G boards assuming you can buy them at that size. Do I need to seal in any way the joints on the roof?
Also I need to install a metal drip edge at the eaves and at the rake edges. I am not sure what product I should use to create a drip edge or do Builders supplies offer a proprietary one?
Mark
Cegidfa
Established Member
Hello Mark,
I am in the midst of finishing my roof, I used 8 x 4 x 18mm WBP ply for the roof (the minimum required by the manufacturers, by the way) All the recommendations both by the manufacturers and by my Trada Timber frame construction book say to leave a 3mm gap round each board. I used the ring shank nails as they were close. It's all about seasonal expansion and contraction. You will rarely see this adhered to anywhere, and by anyone. Knowing my luck they would have buckled and heaved and popped the shingles off, or ended up looking terrible. There is no need to seal the gaps, as the WBP and then the shingles will keep out the weather....unless you make a dog's breakfast of it...which is unlikely.
As to how to get the sheets up on the roof; if two old farts like us can do it with ease, a 'youngster' like you will have no problem :smile:
To see how, look at 'Workshop build, with a difference' in Projects, and wade through it.
As to the rake edge and drip edge; although mentioned in the shingle manufacturers website (IKO in my case) they are not available in the UK........brilliant, nowt like service. If you again, wade through my build, we came up with another way of doing the drip edge, but, we are having a fully ventilated roof...ie. continuous ridge vent as well. This is always recommended for shingle roofs as it reduces the temperature build up in the summer and prolongs the life of the shingles. I don't know if you have given any thought to this yet? The rake edge is going to have the bargeboard slightly higher than the shingles, as the wind blasts the gable end of the workshop. I may also fit a plastic angle piece over the shingles and down under the bargeboard as well.
Have you decided what length nails to use yet? The question is, should they penetrate the roof board, or not? Again, the manufacturer recommend 30mm nails - so they expect them to pierce the board. Once again, many people disagree with this, but this is what the Americans do, and they have far more experience than any Brit. Shingles here, are for sheds, try asking a builder to shingle your house roof and watch the look on his face :shock:
The only option that we had for the drip edge and rake would have been to buy rolls of lead, or sheets of zinc and DIY. The cost would have been astronomical, so we didn't.
I'm sure that Boss will be along to advise you soon anyway, but I thought that you might find another take on things 'interesting'.
It seemed to me, that earlier on, you were reeling under the onslaught of almost too much information, so I kept quiet, as it would have added to the angst. There is nothing worse that having too much information, when one is a little unsure. But it is nice that everyone cares enough to bother with us amateurs. It's what I love about this site - one couldn't ask for more
If you feel the need, send me a PM, and I will do my best to help. We aren't experts, but we are both very practical minded.
Regards.....Dick.
I am in the midst of finishing my roof, I used 8 x 4 x 18mm WBP ply for the roof (the minimum required by the manufacturers, by the way) All the recommendations both by the manufacturers and by my Trada Timber frame construction book say to leave a 3mm gap round each board. I used the ring shank nails as they were close. It's all about seasonal expansion and contraction. You will rarely see this adhered to anywhere, and by anyone. Knowing my luck they would have buckled and heaved and popped the shingles off, or ended up looking terrible. There is no need to seal the gaps, as the WBP and then the shingles will keep out the weather....unless you make a dog's breakfast of it...which is unlikely.
As to how to get the sheets up on the roof; if two old farts like us can do it with ease, a 'youngster' like you will have no problem :smile:
To see how, look at 'Workshop build, with a difference' in Projects, and wade through it.
As to the rake edge and drip edge; although mentioned in the shingle manufacturers website (IKO in my case) they are not available in the UK........brilliant, nowt like service. If you again, wade through my build, we came up with another way of doing the drip edge, but, we are having a fully ventilated roof...ie. continuous ridge vent as well. This is always recommended for shingle roofs as it reduces the temperature build up in the summer and prolongs the life of the shingles. I don't know if you have given any thought to this yet? The rake edge is going to have the bargeboard slightly higher than the shingles, as the wind blasts the gable end of the workshop. I may also fit a plastic angle piece over the shingles and down under the bargeboard as well.
Have you decided what length nails to use yet? The question is, should they penetrate the roof board, or not? Again, the manufacturer recommend 30mm nails - so they expect them to pierce the board. Once again, many people disagree with this, but this is what the Americans do, and they have far more experience than any Brit. Shingles here, are for sheds, try asking a builder to shingle your house roof and watch the look on his face :shock:
The only option that we had for the drip edge and rake would have been to buy rolls of lead, or sheets of zinc and DIY. The cost would have been astronomical, so we didn't.
I'm sure that Boss will be along to advise you soon anyway, but I thought that you might find another take on things 'interesting'.
It seemed to me, that earlier on, you were reeling under the onslaught of almost too much information, so I kept quiet, as it would have added to the angst. There is nothing worse that having too much information, when one is a little unsure. But it is nice that everyone cares enough to bother with us amateurs. It's what I love about this site - one couldn't ask for more
If you feel the need, send me a PM, and I will do my best to help. We aren't experts, but we are both very practical minded.
Regards.....Dick.
Thanks Dick
Great to know I havn't scared everyone off. This site and the proffesionals and ameuteurs who use it are what makes it.
I was going to use cembrit felt shingles. They do talk about ventilation which I was going to do eves to eaves ventilation which I agree is not ideal as heat rises but I am unsure on the detail for eaves to ridge ventilation. That said my build is now completely covered by a large canopy of trees creating a cool spot for it. The only heat it will get is from the ambient air temperature and the wood burning stove that we will fit inside. It will however be prone to a large build up of twigs pine needles and other tree based debris.
The spec sheet for the shingles says 18mm OSB or equivelent and nails that just penetrate the other side of the boards which does seem a little dangerous for those who use there loft space. 3-3.5m ring shanked hot dip galv nails to be presise. My only concern is that the shingles can take the continous pine needle drops and dead branches. I did think of using onduline sheets but they look so commercial.
Thanks for your feedback. Greatly recieved.
Mark
Great to know I havn't scared everyone off. This site and the proffesionals and ameuteurs who use it are what makes it.
I was going to use cembrit felt shingles. They do talk about ventilation which I was going to do eves to eaves ventilation which I agree is not ideal as heat rises but I am unsure on the detail for eaves to ridge ventilation. That said my build is now completely covered by a large canopy of trees creating a cool spot for it. The only heat it will get is from the ambient air temperature and the wood burning stove that we will fit inside. It will however be prone to a large build up of twigs pine needles and other tree based debris.
The spec sheet for the shingles says 18mm OSB or equivelent and nails that just penetrate the other side of the boards which does seem a little dangerous for those who use there loft space. 3-3.5m ring shanked hot dip galv nails to be presise. My only concern is that the shingles can take the continous pine needle drops and dead branches. I did think of using onduline sheets but they look so commercial.
Thanks for your feedback. Greatly recieved.
Mark
On the subject of nail length.. I have been building a office/workshop and decided to use cedar shingles for roof and sides and used the recommended 30mm stainless annular ring nails to affix. This resulted in piercing of the interior of the ply sheathing which in parts is showing a little moisture staining in underside of the roof (fully ventilated + cold), but slightly worrying!
Another side effect is that subsequent insulation of the walls and roofspace has been challenging as I try to push the Celotex against what effectively is a bed of nails...
Has anyone else had this problem?
Another side effect is that subsequent insulation of the walls and roofspace has been challenging as I try to push the Celotex against what effectively is a bed of nails...
Has anyone else had this problem?
Cegidfa
Established Member
Hi Mark,
You mention the danger of protruding nails - will the roof not be insulated, or are you having a flat ceiling with insulation above?
Ah, having re read your entry, you mentioned eve to eave ventilation, so the latter must apply. If you were to use Celotex type board between the roof joists, an airway would be created to allow for ridge ventilation. To cut costs, perhaps use thin rigid board and fill the remaining available space with mineral wool or fibreglass. For ridge venting simply cut a slot across the roof boards, to a given size. The eves gap must be larger than the roof gap, otherwise, down draughting can occur and knacker the natural flow.This link takes you to the stuff that I have bought. It comes in set box sizes, one box is £58 inc vat and del. It would be sufficient for your build. http://tapco-europe.com/ridgevents.htm
Unless you want roof storage, consider leaving it open, as a cathedral roof; that is what I have done. The feel is lovely, and in summer, will be cooler and less oppressive. I used four collar beams only, and it hasn't moved yet. People say that one is required at every stud (600mm or 400mm) but this is for Building Regs only. It will not fall down. My build is regularly subjected to gales, 30 to gusting 70mph, it is solid as a rock....so far :wink:
Regards...Dick.
You mention the danger of protruding nails - will the roof not be insulated, or are you having a flat ceiling with insulation above?
Ah, having re read your entry, you mentioned eve to eave ventilation, so the latter must apply. If you were to use Celotex type board between the roof joists, an airway would be created to allow for ridge ventilation. To cut costs, perhaps use thin rigid board and fill the remaining available space with mineral wool or fibreglass. For ridge venting simply cut a slot across the roof boards, to a given size. The eves gap must be larger than the roof gap, otherwise, down draughting can occur and knacker the natural flow.This link takes you to the stuff that I have bought. It comes in set box sizes, one box is £58 inc vat and del. It would be sufficient for your build. http://tapco-europe.com/ridgevents.htm
Unless you want roof storage, consider leaving it open, as a cathedral roof; that is what I have done. The feel is lovely, and in summer, will be cooler and less oppressive. I used four collar beams only, and it hasn't moved yet. People say that one is required at every stud (600mm or 400mm) but this is for Building Regs only. It will not fall down. My build is regularly subjected to gales, 30 to gusting 70mph, it is solid as a rock....so far :wink:
Regards...Dick.
Dick
I would have loved a cathedral roof but sadly I put up a traditional 20 degree roof with rafters not purlins and so I have had to put low collars in (Ceiling joists) so now I will insulate above the ceiling.
Oh well sadly its turned in to a box, but as it will be used as a office for the Mrs I'm sure the view should suffice.
Mark
I would have loved a cathedral roof but sadly I put up a traditional 20 degree roof with rafters not purlins and so I have had to put low collars in (Ceiling joists) so now I will insulate above the ceiling.
Oh well sadly its turned in to a box, but as it will be used as a office for the Mrs I'm sure the view should suffice.
Mark
Cegidfa
Established Member
Hello Imageel,
We are at risk of hijacking Mark's page, but, did you use a weatherproof barrier under the shingles? I found that for a while, damp appeared after the 'roof wrap' had been done. After a month of warmer weather it dried - to my relief. As to the difficulty with the Celotex, why not leave a ventilation gap, or is the insulation the thickness of the roof joists? I didn't understand the 'fully ventilated + cold' part, as you are insulating the roof?
Another build....we all need photos, to assuage the addiction Don't be shy.
Regards...Dick.
We are at risk of hijacking Mark's page, but, did you use a weatherproof barrier under the shingles? I found that for a while, damp appeared after the 'roof wrap' had been done. After a month of warmer weather it dried - to my relief. As to the difficulty with the Celotex, why not leave a ventilation gap, or is the insulation the thickness of the roof joists? I didn't understand the 'fully ventilated + cold' part, as you are insulating the roof?
Another build....we all need photos, to assuage the addiction
Don't be shy.Regards...Dick.
Hi - yes did not intend to hijack the thread, but the nail length did mystify me :?
The roof has breather membrane under it, but looks like there was some moisture ingress around some of the nail holes...
Rafters are 145 deep so 90mm Celotex leaves plenty of gap for ventilation from soffit up through to the ridge -which is what I meant by cold roof, it was just the walls that I had issues with as the studs were 90mm deep too..!
Regards
The roof has breather membrane under it, but looks like there was some moisture ingress around some of the nail holes...
Rafters are 145 deep so 90mm Celotex leaves plenty of gap for ventilation from soffit up through to the ridge -which is what I meant by cold roof, it was just the walls that I had issues with as the studs were 90mm deep too..!
Regards
Here's my build - have since completed windows and insulation, ready for the electrics- will post some updates later
http://image-electric.com/home/albums-9
http://image-electric.com/home/albums-9
The hipped roof was a bit fiddly - I used the calculator mentioned earlier in this thread http://www.blocklayer.com/Roof/RoofEng.aspx to do the calculations, and cut them either on my bandsaw or by hand. I've never done this before so it was a bit of a learning curve but worked out ok. Would have been a lot easier with a sliding mitre saw, but I was on a tight budget after paying for the shingles...
- I got them from http://www.ajsmith.uk.com/cedarshinglesframes.htm ~£1230
- I got them from http://www.ajsmith.uk.com/cedarshinglesframes.htm ~£1230
Cegidfa
Established Member
Hi Imageel,
Very nice build, nice to see a hipped roof. The cedar looks rather good too. What size is the workshop...it's far too posh to be a shed :smile:
How long has the roof been finished? I still feel that it is residual damp that will dry in time..well..I hope it will!
Regards...Dick.
Very nice build, nice to see a hipped roof. The cedar looks rather good too. What size is the workshop...it's far too posh to be a shed :smile:
How long has the roof been finished? I still feel that it is residual damp that will dry in time..well..I hope it will!
Regards...Dick.
It's 4x5m but only 130ft from house line so wanted something solid and fairly well insulated to cut down noise particularly whilst planing :lol: The roof has been on since last August but as I only get to work on it at weekends progress has been slow, and with no proper workbench (B&D Workmate) making the windows particularly the cills has been challenging..
Still a bench is in progress, but need to finish th einsulation 1st
Still a bench is in progress, but need to finish th einsulation 1st
Cegidfa
Established Member
Hi imageel,
Hmm, if the roof has been 'sealed' since last August, it should have dried out by now? Is it wise to fit the insulation yet, until the reason is found?
You wouldn't half be peeved if you had to remove the roof lining later
Any chance of a window construction chat, with pics of course, I for one would be very interested in the procedure. Mine are non opening, so not very challenging.
Regards...Dick.
Hmm, if the roof has been 'sealed' since last August, it should have dried out by now? Is it wise to fit the insulation yet, until the reason is found?
You wouldn't half be peeved if you had to remove the roof lining later
Any chance of a window construction chat, with pics of course, I for one would be very interested in the procedure. Mine are non opening, so not very challenging.
Regards...Dick.
I'd replaced windows on my previous house made by myself out of necessity - I couldn't afford to buy!
I found a copy recently of the 2009 Trada doc on wooden windows which I used to design the ones for the shed - can share with you if you wish.
It's funny isn't it what drives us to this - I have never built a shed before, what I prefer to do is finer woodwork, cabinetry etc, and I found it really difficult working with large sections of timber that were not square, that were so large they needed a home-made set square 6ft long (3x4x5 triangle) to align correctly etc etc.
For me it was an eye opener to the different skills required, and hats of to all you construction guys who do this every day.
For me the finished workshop will enable me to get on and refurbish a more-or-less untouched 1930's property where everything needs replacing!
Here's an example of what I am more used to constructing in my spare time -
Cheers
I found a copy recently of the 2009 Trada doc on wooden windows which I used to design the ones for the shed - can share with you if you wish.
It's funny isn't it what drives us to this - I have never built a shed before, what I prefer to do is finer woodwork, cabinetry etc, and I found it really difficult working with large sections of timber that were not square, that were so large they needed a home-made set square 6ft long (3x4x5 triangle) to align correctly etc etc.
For me it was an eye opener to the different skills required, and hats of to all you construction guys who do this every day.
For me the finished workshop will enable me to get on and refurbish a more-or-less untouched 1930's property where everything needs replacing!
Here's an example of what I am more used to constructing in my spare time -
Cheers
mm not sure what happened there.. link should have been http://www.image-electric.com/home/images-103
Dick -if you wish I'll send you the doc I worked from. Will see if I can upload some more pics of the windows later.
The staining I was referring too happened soon after the cedar cladding went on, so I presume it was just latent moisture in the materials, it hasn't got any worse since and although I'm in part of the driest part of the country we have had significant rain since last August
Dick -if you wish I'll send you the doc I worked from. Will see if I can upload some more pics of the windows later.
The staining I was referring too happened soon after the cedar cladding went on, so I presume it was just latent moisture in the materials, it hasn't got any worse since and although I'm in part of the driest part of the country we have had significant rain since last August
Cegidfa
Established Member
Hi Imageel,
It's good that the moisture was as thought, and has dried out. How are you managing, fitting the insulation to the Fakir's bed, AKA the roof
Having looked at your pics of the house, you are ahead of me in 'arboreal manufacturing.' The only room here that is done, is the bathroom; that just leaves the kitchen, dining room, living room, landing/computer area, three bedrooms and oh yes, knock down the utility room and build it larger. Why do we put ourselves through this torture :wink:
I would be very grateful for a copy of the doc, thanks.
Regards...Dick.
It's good that the moisture was as thought, and has dried out. How are you managing, fitting the insulation to the Fakir's bed, AKA the roof
Having looked at your pics of the house, you are ahead of me in 'arboreal manufacturing.' The only room here that is done, is the bathroom; that just leaves the kitchen, dining room, living room, landing/computer area, three bedrooms and oh yes, knock down the utility room and build it larger. Why do we put ourselves through this torture :wink:
I would be very grateful for a copy of the doc, thanks.
Regards...Dick.
