Extension Build

[Carrerahill]

Well today was a bit of a milestone for my extension project as the structural engineer has approved the existing foundations and walls which is great, I guess in a way that's us now out of the ground albeit the next stages are demolition.

 

So here is the story, you may know from my other post there is a garage being built, well it will once planning comes through, planning is joint with this extension - planning didn't assign our application to an officer and well that was 10 weeks ago! It will be with me in 4 to 5 weeks I am told! Oh good!

 

So the build is an existing sunroom being converted into a proper room which will become the kitchen - our back garden is about 1500 below floor level so the sunroom was obviously built up to match FFL in the existing house, so there are decent founds and a good going block cavity wall, so my plan was to reuse all of this. My architect put in my building control application at the same time as the planning and it seems to be going slightly more smoothly. The BCO came back and asked for a certification for the founds, the SE visited tonight and has confirmed he will be happy to write to BC and confirm they are suitable for my proposed build and gave me some good tips and advice on how to do some bits and pieces - one of them was based on a suspicion that the existing floor joists are held up by joist hangers fixed to the inner block wall - this leaf will be demolished to top of joist level anyway as the timber frame will sit partially on the block and the rest on the timber frame, if hangers have been used he advised for the sake of 15 or so joists I should demolish the inner block wall down an additional block and run new joists over the top of the wall so it sits on it rather than hangs from it so that the loading is not such that it is trying to tip the block inwards. Made sense to me and is something I can easily do myself and I don't mind having to remove the joists because they will work perfectly as studs if they are OK or if a bit rough in the garage build.

 

So I am expecting BC approval very soon and hopefully the build can commence mid to late August once planning consent is granted.

 

So I am starting to think about the build and how I will do it, my plan is to get the existing Sun Room removed and get the walls demoed to the various heights etc. myself, and make good any bits and pieces, I will also then be able to either confirm the joists are fine or run in new ones. Then I was going to build the timber frame myself, I am very confident about the actual building, but my issue is experience of BC approved practises and accepted methods, once I am happy with these through talking to you guys, my architect and my structural engineer it won't be an issue, I just need to check and double check all my dims and make sure it's all spot on, so herein the first question, the frame will sit against the original house in two places, do I run a piece of DPM between the house and the first stud then fasten the stud to the house with the same fixings as speced for the roof beam? I cannot actually see a detail for this anywhere, I assume it gets tied into the existing wall?

 

Once I build the frame I assume I can then just fix my wall plate and lay in my joists - now here is the second question, I asked for 2 skylights in the roof, I looked at the drawings at the time on a mobile as I was on business and said yeah looks fine, mistake! My architect didn't include the skylights, so how can I get these in now that the BCO is about to approve the drawings... Can I email him after approval and discuss - I would say I will sister the beams either side and affix the tie beam in with all the correct metalwork. Do you think he will accept it at that and let me go for it? What is the script with variations with BC.

 

Thanks

Edited June 22, 2017 by Carrerahill

[MikeSharp01]

The skylights will probably need planning permission, rules may differ so need to check with planning and see if you can squeeze it in under the wire, as it would be a material change to the permission granted, but I doubt the BCO will be worried if your structural engineer signs them off.

[Carrerahill]

Thanks for your reply Mike. The girl from planning has just left after doing her site visit and said that I can send her an email with the skylights shown on the roof in a drawing and she will OK them as she saw no reason they would cause an issue - overlooking issues etc.

 

Anyway, good news is she says I can call on Friday and should have my answer with the official letter (paper? digital?) following soon after, she says what I am doing is pretty clear-cut and I can expect to be granted permission. Pretty pleased with this as the neighbour consultation only ended on Monday!

 

Good news, as the excavator rolls in on Saturday morning!

 

 

 

 

[Carrerahill]

Hi guys. I have building warrant and planning now so I can think about starting very soon.

 

I am trying to sort out the timber frame aspect of it just now and note the warrant drawings call for Tyvek Reflex and 2.0mm breather membrane to BS4016 - so I guess I just wrap the frame with something like Tyvek housewrap then wrap it in the Tyvek Relfex. 

 

I am tempted to send the commencement letter ASAP so I can just start firing up the frame but want to make sure I can get it wrapped ASAP so need the right stuff.