Flat roof advice please

[176tvw]

Hi All,

I'm looking to build a flat roof utility room between my house and garage, so basically enclosing a courtyard, dimensions 2.4x4.6m. I will be utilising an existing doorway to access it from the house, but will be installing an UPVC exterior door, so as to avoid planning/building reg as it is only a stop gap until we can afford to extend properly. The wall with archway in pics will be demolished. Front wall of utility will go just inside of the green soil pipe, and back wall just inside of the garage side door.

I had planned to put a 5x2 ledger beam along the garage and house wall with a 1:80 fall, then 5x2 joists at 400mm centres on hangers. OSB board, then rubber membrane roof. Garage roof would drain onto the new flat roof. Floor will be same principle, with damp proof sheeting underneath, and up the side level to DPC on both side. . Front and rear walls, weatherboard, battens, breather membrane, OSB, CLS frame. All insulated with 100mm celotex between structural timbers.

Anything horrendously wrong with any of that? I'm aware of air gaps/ventilation being required and currently reading up on that.

The house side already has a DPC the full length of proposed extension just above roof height due to old doorways/windows, so I'm assuming this will avoid the need for a cavity tray?

My first challenge is the height, defined by the garage roof and existing door way. I don't want to get too complicated, so would prefer not to have to interfere with the garage roof too much. The horizontal timber across courtyard in pic1 is at the height of joists. This leaves me with two problems
1. The garage side ledger beam (see 2nd photo) will have to fix to the existing timber wall plate, and only the top course of brickwork. Will this be OK? best method of fixing? spacings? I was going to use studs and resin at 400mm, until I realised I couldnt use only brickwork.

2. The house side is just crossing the top corner of the existing door way, so fixing/spacing will be difficult

Any help, advice, or better ideas much appreciated. I'm hoping to complete this whilst I'm off on 2 weeks paternity leave, and I'm 2 days in so time is of the essence as we need somewhere to park a pram and store assorted baby paraphernalia.

 

[nickjb]

I might be tempted to keep the wall with the archway. What you are doing will need building regs and most likely planning permission whatever door you fit. If you want to do it anyway then best to keep it out of sight.

 

[176tvw]

Can I ask why? Because it joins the garage?

 

[nickjb]

I'm not an expert so you'll need to do your own checking but I think it would be classed as a covered yard. That'll make it exempt from most of the building regs but you'll still need to conform to part p and there are some restrictions depending on how it impacts on the existing doorways.

As for planning there are a few requirements it'll need to meet to be permitted development (possibly being to the side of the house might be an issue). Ironically I think it is easier for a proper extension to fall under permitted development.

 

[176tvw]

OK, so how about if it had a separate external wall, with a walkway between it and garage, this was my other option anyway?

The existing doorway is of little concern to me, regardless of regs as it is redundant, and if you look closely you will see an external tap and a drain plumbed through it, as the washing machine and tumble driver currently reside in what was a porchway.

Part P - the intention was to simply move a socket by drilling through from inside the garage wall to outside the garage wall (inside new utility). It is RCD protected, but given the use of shower cable externally (as per photo) I guess would fail anyway despite having been like this 7yrs+ that I've been here. I would likely replace/reroute internally as part of the built.

 

[ree]

OP,

i dont want to get involved in this thread but why not post a brief question in the Regs and Planning forum?

FWIW: move the exposed timber into the garage or under a tarp - keep it off the deck, and separate and stack with spacing "stickers" for drying out.

 

[terrypin]

Sam, it would appear your first day and first 3 posts are loaded with links to/for the same company, hardly impartial advice.