Building regs drawings - my attempt

21 Oct 2014
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West Midlands
United Kingdom
I'm intending on building my permitted development side kitchen extension on a very tight budget. All savings are to be made on labour by doing the lot myself (other than gas and electric). Limited building and design experience, but handy and determined!

Ive attempted some plans to give myself a better idea on construction and also to submit to building control. Having never done this before, I'd appreciate some critique so I can amend what is necessary. Cross section is along the line N-S on the plan. Just for reference the garage is attached to my house which is not shown.

Any advice appreciated

Kitchen building reg plans 2.jpg building reg drawings foundations.jpg building reg drawings overview.jpg building reg drawings roof.jpg extension exterior front.jpg extension exterior rear.jpg extension exterior roof.jpg
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Current layout


  • Kitchen and outbuilding current layout.jpg
    Kitchen and outbuilding current layout.jpg
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Take the pretty rendering off, it has no value for technical plans. Use one of sketchup's basic outline templates. And take off perspective in plan views as it distorts the view.

You don't need to dimension everything, just the main structural dimensions. That "401mm" dimension is odd, and if they should be 400mm spacing to meet span table guides, then the dimension is to the centres not edges

The other thing that stands out is your pitched roof rafters. They are not framed properly, with no support to the back/top of the rafters and no tiagulation to the front of the rafters. You need to stop the flat roof insulation where is meets the vertical timber and construct off the flat roof joists, as you can't build off insulation.
I am not sure that this would qualify for PD in its current form due to the porch like forward projection.
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Thanks Woody. I shall have a look at your suggestions. The pitched roof rafters sit on a ridge beam at the top that will span from the current kitchen wall to the far wall. The base sits on the wall plate. The wood sitting down on the flat roof insulation is just to close in the back. Does it need to be triangulated if it has a fixed bearing top and bottom?

The 401mm gap is my crap drawing! 450mm centres. 2" wide joists

Rich. Why is it not PD? The little porch does not extend past the front elevation of the house. It is set back. Kind of a side/tradesmans enterance.
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What workflow are you using to annotate the drawing, Pil? Is that sketchup with layout annotations, or Sketchup with something like FlatLeader annotations?
I've seen those diagrams before. The new porch bit is behind any principle elevation of the house. i.e will e set back furthest.
Sorry pilsbury, the 'principle' elevation follows the front wall of your house, it is not a straight line from side to side in line with the bit that is nearest the road. Your porch is not PD. So you need to shrink it to 3m2 max with a maximum height of 3m if you want to do it under PD.
I'll post a pic of the house tomorrow morning. That new porch is further back than any part of the front of my house.
Yes, garage doors face the road. The new porch is set back. As per the diagram it will be behind the principle elevation line.

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