Extension advice

[rsbhj]

I am looking to extend my property.

Rear a 3x4m extension to create a kitchen/diner

Side a 3x8m extension including a garage and bedroom

I ideally wanted to build a 2 storey extension to the side but funds will not allow at this stage, so my question is what type of roof for the side with the view that I will add the top level extension at another stage maybe in 5 years or so... pitch tilted or flat and more importantly how much cheaper is a flat roof? At the moment my quote is £1300sqm (tiled pitched roof)

I myself would say flat roof is best option as one it will be cheaper, two easier when the day comes to build on top of

 

[Blagard]

While I would agree that a flat roof is cheaper, it needs to have roof joists sized to suit floor use later and wall foundations suited to two storey. Use either planted on firing strips for roof falls or have the falls built into an insulation layer (warm roof style) and use a floor grade board for the roof deck.

It may be the planning department could have some say in the matter so check that out as well.

 

[mandm65]

Side a 3x8m extension including a garage and bedroom

At the moment my quote is £1300sqm (tiled pitched roof)

If above rate per sqm is correct then how much the total cost would be?

BTW i am also contemplating my options for rear extension with the same view of going double when the funds are available.

 

[Architexeter]

As Blagard says sort out the height and joist size so that the joist can remain in situ when you choose to extend up. Make sure they are floor joist sized and the right level for accessing off of the existing first floor. This will save messing around with the ground floor room ceilings when the time comes. You should be able to do this with both flat and pitched roof options.

Flat roof may well be cheaper but paying for the roof tiles now will mean they can be reused when you build the two storey part so its not that simple as there is a slight cost saving down the road. A pitched roof will also be more sustainable as the flat roof membrane would end up in a skip whereas the roof tiles can be reused.

If for any reason the two storey part takes longer to afford that you calculate today or never gets done you will have a prettier house in the meantime.

Hope that helps.

 

[mandm65]

thanks mate, pitched it is then, for me anyway, i am convinced!

 

[jeds]

All the above but a significant factor would be that (going with a pitched roof) you could probably achieve everything without the need for planning permission. But not with a flat roof!

 

[rsbhj]

mandm65 - If above rate per sqm is correct then how much the total cost would be?

BTW i am also contemplating my options for rear extension with the same view of going double when the funds are available.

The total cost for the 2 storey as ground 25 x 1300 and first level 25 x 900 = £55k +20% VAT and then I would have to redo the kitchen and bathroom as well as a new ensuite so in total I was looking at approx £80k for that, and then decor costs

The rear is 12 x 1300 +20%VAT, if I could afford to do the 2 storey in one go then I wouldn't do this although I would like to have it, but if doing it in 2 stages then if is needed


To the rest -

So if the flat roof is alot cheaper option then I need to look at making sure the roof is built to allow for building on top in the future, and there is also a few planning issues and possible house insurance issue too look at.

My thinking was that if it was not possible to complete the build in the future then I would put a tilted roof on it then or sell it with the planning permission in place to build on top.

I had considered the idea of reusing the tiles for the roof but the only thing here is that it might looking a bit patchy if I didn't have enough to do the complete front or back of the roof with reused tiles.

I am still in 2 minds with what too do and will see what the cost come back as and what the builder recommend, I just thought in the long run it might be easier to build on top with a flat roof rather than removing a tilted roof.

Thanks for the advice and replies and if anyone else has any good info please share

 

[mandm65]

The total cost for the 2 storey as ground 25 x 1300 and first level 25 x 900 = £55k +20% VAT and then I would have to redo the kitchen and bathroom as well as a new ensuite so in total I was looking at approx £80k for that, and then decor costs

The rear is 12 x 1300 +20%VAT, if I could afford to do the 2 storey in one go then I wouldn't do this although I would like to have it, but if doing it in 2 stages then if is needed

Thanks for sharing the info, your cost seems in line with what i was quoted for mine 6x6M extension so my total cost is approx. 48K+VAT, like you i need new kitchen (8K), new bath (5k) and new boiler/Megaflow (5K). I also have additional cost of redoing the existing dining/kitchen (removing walls and putting some beams so i need to have another 5K put aside. Consequently we have no option but to postponed the second story to a later date and like Architexeter said if the second story never gets done we will have a prettier extension, beside I just love pitched/tiled roof . Our architect has proposed beam in the existing roof structure to allow for the second story to be added with less hassle.
Have you considered adding any skydome type opening in your roof?