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Loft Conversions

Loft conversion with velux window - convert to dormer - what's involved?

Hi. Not looking for any estimates on this, just an idea of the work involved which we'd need to consider.

We have an existing loft conversion - two bedrooms, one with a dormer, one with a velux window. The velux window needs repairing and now we're thinking about it my husband has expressed an interest in installing a dormer window instead, to open out more space in the room.

On average, how big a job is this in terms of steps involved, disruption, and time taken (quite apart from the cost, which clearly isn't something we can go into here?). I'm thinking

- drawing up plans
- permission?
- scaffolding and permission from neighbours to put it up
- removing existing window, putting a big hole in the roof (!), adding in walls and roof, installing window...
- plastering and decorating

Can anyone correct / expand on this, and let me know what it's like living through such a job and how long it can take, from experience?

Thanks in advance.

2 Answers from MyBuilder Loft Conversion Specialists

Best Answer

Plans would cost approximately £ 800, you may need planning permission for the dormer, £ 150 payable to your Council and you would also need building regulation approval £ 300 approx. The dormer would add additional loadings to the existing loft floor structure so you may need to upgrade the existing loft floor to take the additional loadings, so it can be quite disruptive.
Pete Watkin
Aztech Architecture Ltd


Answered 9th Sep 2012

As you already have a dormer it may be assumed that you also have a steel ridge beam installed, which is the costly / disrupting aspect.

You would need Building Control approval and this can be done on a Building Notice.

Again the assumption would be that you already had a party wall notice with the first conversion and therefore thois would not be required scondly and unless you are proposing to install the dormer on the party walls this would not be required again - assume the dormer would be installed roughly midd;le of the roof - if not party wall notices would be required.

Then basically the works are as you describe, there would be a requirement to install roof jopists to connect to the existing roof etc which would cause disruption.

Would suggest you ask original architect and engineer as to the feasibility in first place.

Time wise 3 - 4 weeks, disruption - high, cost approx. £4500 (subject to requirements and complexity)

G&H Building Services


Answered 9th Sep 2012

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