Permitted Development: Side Dormer to a chalet style property

26 May 2019
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United Kingdom
Dear all,

We were hoping to get some advice on the following.

We are the owner of a 1930s chalet style property (see attached image), we are intending to build a dormer on the side (at the first floor) to create an additional bedroom and family bath.

We have been advised by the builder and structural engineer that we can do this under PD (we dont exceed any of conditions for volume, height etc), we therefore understand that we would need to apply for "prior approval". However there are couple of things we are confused about.

1. Due to the less than standard design of the house are we actually doing a loft conversion (as we are converting loft space into habitable space, and adding a dormer so we can properly stand up!) or is it a single story extension (but on the first floor)?
2. The prior approval form for a single story extension refers specifically to rear extensions, however ours in on the side! We cannot seem to find a prior approval form that specifically deals or mentions loft conversions.
3. As the work we are doing is on the side will we require full planning?

Unfortunately our local council will not provide any feedback without making a full planning application! (they won't do consultations over the phone) and as we are doing this all on a budget we would prefer not to have to hire someone!


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You don't need planning permission for that - it's classed as a 'roof enlargement' which is permitted development as long as it is no greater than 50m³, not on the front of the house facing a highway, doesn't go above the ridge, and goes no lower than 20 cm to the edge of the tiles just above the gutter.

(Prior approval is not relevant to this type of work - it's only for single-storey rear extensions).
Thank you Tony for responding so quickly! This is great to hear, we're just a little confused as to whether we still need to notify our council and neighbours about this permitted development- as the only form we can find in which to do so is the form for prior approval which obviously isn't the right thing for our circumstance. Logically we would have thought that we have to inform someone that we're going to do works!? (we've already taken brownies round to the immediate neighbours to let them know about our plans)
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Forget the prior approval forms - they are one of the many forms printed for various types of planning application - and you don't need planning permission at all (unless you are in a conservation area?).

You don't need to inform any neighbours.

What you DO need before starting is to make a Building Regulations application. This is concerned solely with the structural side of the build, and the building inspector will check compliance with the regulations on things such as beams, roof insulation, fire safety etc. On satisfactory completion of the work, you will get the Certificate.

You have the choice of using your councils' Building Control service or you can use an Approved Private Building Control firm. Google 'building control' to see local firms. If you use a private firm, they will notify the council that they are undertaking the building control function, but other than noting that, the council will have no input.
Costs vary quite widely, but a ball-park figure for a dormer in my area is £5-600.
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