gavztheouch

This makes a lot of sense. Wish I had a nice simple roof with no dormers.

Thanks, this is what I had in mind about. I did have an additional membrane over the sarking boards but I see how this is not helping. Vmzinc have a detail for this and they do not have a membrane over their sarking board but they do over the plywood. I agree I would not use standing seam again. My biggest dislike is the hard to repair factor. I have 4 flat roof dormer windows that will no doubt leak at some point, could be a nightmare waiting to happen

Im about to start building my ventilated deck. I prefer to handle sarking board vs large sheets of 18mm plywood. I noticed Vmzinc say you can use sarking board under their Zinc. Just wanted to know if anyone has used this method. How did it go? Are there any disadvantages? Some advantages I can think of are. 1. increased ventilation behind the Zinc. 2. About half the cost of Marine plywood, the best ply option, Still slightly cheaper than acceptable plywood. 3. No risk of delaminating 4. May be more forgiving if your 600mm rafter centres are not perfect. You could cut the wood back to the next rafter. Im not sure about this one. 5. Easier to see rafters to nail. 6. May be possible to do the job myself or with a little help from my dad. Disadavantages. 1. Wood thickness may vary a lot board to board. 2. The boards ends may split easier than ply 3. Less coverage per board and potentially more cutting/measuring 4. Badly warped/cupped boards may need to be discarded. Some boards may warp on the roof. Do I need to double nail each joist to stop them coming up as they dry?

EcoCocons Panels look good. This house was built with them https://www.passivhaustrust.org.uk/projects/detail/?cId=88

Yes I will be tapping the membrane to the foundation upstand. The folded up dpm or any extra bits of tape and membrane were meant to be extra barriers. Now that I have thought about it more I will revert back to the original detail of using just the membrane to stop the water getting through to the sole plate. Like you say keep it simple and try and do it well. Maybe I will monitor some choice points of the wall in times of windy wet weather to see if I can see any water getting through. An ideal solution would be a wire or some type of detector that could detect water at the sole plate. Then we would know to fix the membranes/window taping

Which option did you go for in the end?

I really like this idea but now I'm not sure I should do it. My concern is if any water finds it way to the bottom of the wall, the external membrane is trapping the water from getting out as it is taped to the upstand. There is however a possible path out as the gaps between the isoquick as quite large, some almost 10mm. These could work pretty nice as drains. If I put the tape marked in orange this will bridge over the gaps and stop the water. My next though was keeping these drains clear. I think I might have to prime the cut edge of the wood fibre board and run a length of pro clima 100mm wide vana tape over the edge to stop all the fluffy bits of wood coming off and washing down into the drain.

@Iceverge Im about to start adding the external wood fibre to my build. Im interested to hear if you still think stapling the dpm to the wall is a bad idea? I should clarify the dpm will be folded up against the racking board which is behind the wood fibre so it would need to get in between the wood fibre and the racking board which I guess would be possible. To prevent it diverting any water towards the sole plate I was planning on adding some pro clima tape to hold it against the racking board making it even more unlikely to divert water into the wall. If I could go back in time I would have maybe stapled it against the studs as this would be very unlikely to have water running down the studs. I didn't do this as the nails for the racking board would go through the dpm.

Currently leaning toward these Modified PU liquid rubber roofs. A very similar method to GRP but less sensitive to rain and temp during install and flexible once set. Looks like a better option than GRP. https://www.bmigroup.com/uk/ultima/

Many thanks Kelvin, Yes it seems flat roofer are hard to find and most people don't speak highly of their work. Ive been training myself to weld various single ply membranes but I would be able to buy most weldable single ply membrane made of stuff like PVC unless I do a course. I would be willing to do the course if they will let me.

Hi @Kelvin did you manage to find a Scottish installer?

157.414_DormerDetail.pdf Just received the details from the architect. First thoughts are it is very complicated for 4 very small dormer roofs and will be a lot of work. I don’t think the circular outlet has enough area around it to weld/glue too. There are also a lot of varying surfaces/angles and junctions in a small space. It’s annoying details like this are taken through the simplest part of the roof and do not take into consideration the more complicated areas like the upstand corners transitioning into the top of the upstand area. The upstand corners need to be detailed with a pigs ear or a remolded epdm piece this would be right in the way of the outlet. Then we have the issue of the area in the video where the pitched/flat and in upstand meet. A lot of these issues could be solved with grp. How does glass fibre cope with movement?

157.414_DormerDetail.pdf

Having a go at this in resitrix epdm. I think I need to cover both upstands in one go across the whole width of the dormer. Maybe GRP is the way forward, getting it dry enough at this time of year for GRP could be an issue. I try again with the resitrix and see if I can get it better.

This is a hard one to explain with just words. So I made a model to represent the problem. This flat roof dormer connects to a 35 degree roof clad in metal. I am having a hard time work out how to waterproof the area where the upstand for the parapet meets the sloping roof. Open to changing the roof material and design. Would much rather not have these flat roof dormers but I am here now and need to make the best job I can. World appreciate any ideas and thoughts

Probably can do that. until I put a straight edge across its hard to see how bad it is now. If it doesn’t get much worse then it will be fine for carpets. Might need to plane down the bathrooms if they are tilled or vinyl.

Flooring is down. I used egger protect which has a coating on it to give 60 days protection. Unfortunately the joiners have used half the amount of foaming glue needed so the glue has not sealed the boards and already after a couple of days the edges have swollen. Pretty annoyed as the flooring is something you can’t really ever replace as it’s under the first floor wall and glued to the joists. Fingers crossed it emerges out the other side of 30 days getting the roof on in ok shape. The joiner said he knew how to fit it and he has done it many times. We discussed the importance of a seal on the boards so I felt comfortable I didn’t need to check the installation instructions to check how much glue we needed. In hindsight the only way I think to make sure it was done right would have been to check the installation instructions and then worked with them to make sure it was done right. Exhausting having to second guess everything.

Flooring started to go on today. I had to pre-insulate the floor round the edges where the wall sits on top as this will not be accessible later on. I used hemp insulation here as it was the closest to wood fiber I could get at short notice in the sizes I need

This is why I love forums. This seems like a great idea to give extra protection incase of failure, I don't think I would have though about doing this. Some other ideas I might incorporate would be to 1. staple the concrete DPM to the racking board to give an extra back dam. 2. On the lowest/bottom wood fibre board tuck external membrane inside the tongue and groove of the board. This means if any water makes its way under the membrane at the top it will never get past the last 600mm of membrane and boards. It means wasting a some membrane to achieve this (cutting standard width down to 800mm or soo. The alternative is to lap the membranes in the usual way by this would rely on the membrane being taped to the wood fibre for 50 years or so without failing. Since in Scotland we normally have a brick cavity in front of our timber frames I think it worth thinking about ways we can engineer our walls to be more robust.

One of the steels in position. We used my dad’s digger to lift the beam in position. Reckon it weights around 300kg

Preparing the steel that will sit inside the floor assembly. Needed to metal screw a 5x2 piece of wood with a plywood packer to the top, drill some mounting holes and also cut to length.

Hello, I have a similar problem. Here is my condition.. Restrict Occupation: The occupation of the dwelling hereby approved shall be limited to a person solely or mainly employed, or last employed, in connection with the Hay Barn on Land 255 Metres North of (Parents) Farm or a dependant of such a person residing with him or her, or a widow or widower of such a person. Pretty nasty as it connects my shed to my new house and makes it impossible to sell the house by itself which is the definition of an issue. The second part of the below bullet points is new, i've been checking this for years on the HMRC website and never seen this before. You are not eligible to use this scheme if you’ve: constructed a property that, because of a condition in the planning permission (or similar permission such as a planning agreement), cannot be disposed of or used separately constructed a property that either you, or your relatives, do not intend to live in but intend to sell or let out or use for any other business purpose — a business purpose also includes a dwelling built because you need to live where you work What really bugs me is my house is the only one in my area that has this specific condition. All my peers who are also building now on their parents farm land have no conditions attached. I think I caught my local areas planning department in a transition phase when they moved from applying general ag tie to now zero ties. Somewhere in the middle they decided to make their own custom and specific ties which look to be very hard to reclaim the vat on. My plan was to get the condition removed via a section 42 form, I have 1 month left before my 3 year window of opportunity closes to do this. My fear is, if I get the condition changed, it will trigger a new planning approval and hence I may not be able to claim vat back on all purchases I have made to date, roughly £100k. @Shanemac I would love to hear your experiences

Rim beam, Joists and Glulam arrived today. Can't wait to start building the floor.