Extensions Question

How do i begin the process of putting a dormer window in along the back of my house?

Basically, its a 1960s chalet bunglaow type house. At the rear of the builing a dormer window has already been put in for the master bedroom. This leaves quite a large void of approx 3-4ft of voided area behind the bathroom. At the opposite end of the house next to the bathroom a two storey extension was built and due to the chalet bungalow style, has a sloping roof at one end of the room. I would like a dormer window to make the bathroom larger and also to square off the second bedroom next to the bathroom. How do i go about beginning this process? Do i need plans drawn up prior to getting a builder? Or does the builder just pop round have a good old look and quote from this? The building to the right and left of me are of the same build and all have dormer windows across the rear of their properties. I also have a flat roofed conservatory undearneath the area that requires the dormers, is this potentially a massive problem that could halt the process before it all begins? Also i understand the costing maybe how long is a ball of string, as you can't see the property. But does anyone have a rough ball park figure?

Sorry if these seem like silly questions, but this is my first home and I am wary of having the wool pulled. Any help would be greatly appreciated.

6 Answers

Best Answer

you will nee to start by asking your planning department if you need permission, if so you will have to get an architect yo draw up plans to submit to planning and building regulations( 2 seperate applications and costs) if approved then post a job on this site to get quotes from builders in your location,regards Terry.

Answered 19th Apr 2011

tm property services

Member since 9 Mar 2011

First you will need plans and building regs, This could open a hole new can of worms as you are altering the structure of the roof, its possible you already have steel inplace with you already having dormer window but if not this will be required, the roof will need strengthend doubling up on rafters.
price would start from £2000.

Answered 20th Apr 2011

d.robertson builders property & loft conversions

Member since 26 Apr 2009

sounds like what you want to do will fall within your permitted development rights. you will need plans and calculations thats the first job. once all the paperwork in place then you can buld. this could take a little as a couple of week but no more than 8 week and it shouldnt cost more than £1200. if you want to know more we do this all the time and would be happy to advise you

Answered 20th Apr 2011


Member since 27 May 2010

I would strongly recommend that your first port of call is to contact a architect.He will draw your plans to scale. He would give all detailed specifications that have to be adheered to. Once you have your plans and design in your possesion you must apply to your local authorities for planing consent this normally would take 8 weeks.In the mean time give a set of plans to each builder who is interested in your job. The builder now as every thing in front of him enabling him to quote for the job knowing exactly what the job entails.It would be impossible as you can apreciate for any worthy builder to give you a quote not knowing exactly what as to be done. Best of luck with your project

Answered 19th Apr 2011

Goldcrown Building Contractors

Member since 19 Nov 2008

No feedback

I would say, if your neighbours have done similar, then a precedent has been set, therefore I cant foresee any reason why you cant.
You will need an architect, maybe structural engineer, you will also require planning permission and building regs.
Best to engage the architect first, who will advise intially, he can then do your plans and sort out the regs, he should also know a s/e
The architect should also to give you a guide on the costs.

Answered 19th Apr 2011


Member since 29 Oct 2008

hi you dont necesseraly need plans or building regs you can do this under a building notice.you will definatly need a structural engineer though.you will need to contact your local council as to planing but you may not need that either depends if it can be seen from a passing road.Any decent builder should be able to price without plans. engineers report will state any steel or truss work and rest is quite simple.hope this helps

Answered 20th Apr 2011

total residential property services

Member since 17 Dec 2008

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