Glazed Gable Over Bi-Fold Doors?

[pete1980]

Hi all,

We are having plans drawn up for a ground floor extension. We are going to go with bifold doors on the family area, but are in two minds whether to go with a small glazed gable roof above above the bi-fold doors, so I was looking for a second opinion on potential costs and added value please?

The house is a 1960s semi and we are looking to go back 4m across the width of the house, with a kitchen one side then open plan family area the other.

I have seen the following article where something similar was done on a detached house and it looks stunning
http://www.homebuilding.co.uk/2014/06/04/glazed-kitchen-extension/

However I am not sure about costs, and whether it is an overkill for a semi-detached house. I am doubting whether it will really add any value to the house over velux style windows as and when we sell (no plans to move any time soon though), so would be for our own enjoyment only.

I understand the glazing itself would add around £1500, but have heard some suggestions that there would be a lot more significant on-cost to the roof design with additional steelwork required, and could end up being in the region of £8000 extra in which case we are less keen! Does this figure sound about right please? And does it sound a fair assumption it won't add a great deal of value to the house?

I am asking now as I wanted to get an idea before we submit the planning application, and are not yet at the stage of asking potential builders. I have also attached a couple of mock-ups I did in sketchup. The adjoining neighbour is on the same side as the gable roof / bifold doors but not shown here. They are planning a similar lean-to extension in due course so we would want to keep that as the 'main' roof style and build any potential gable out of it else it will look quite odd.

Any thoughts or opinions greatly appreciated!

Thanks,
Pete

 

[pete1980]

The mock-ups I did are below, which didn't embed in the above post for some reason. Thanks again in advance for your advice.

View media item 96761View media item 96760

 

[tony1851]

Can't see your sketches, but can say that these designs are expensive and generally only appear in the glossy Sunday supplements.

The main issue is supporting the ridge beam over the glazed gable. The usually entails some sort of welded steel frame
designed to carry the load down each side, which is expensive in terms of fabrication costs.

You will also go well-over the normally allowed area of glazing, contrary to thermal insulation regs, and will have to
incorporate energy-saving measures elsewhere, = more £££.

Keep it simple!

 

[drpepe]

We had one of these gable windows in our original extension designs, then rapidly removed them once we found out the hassle & cost (as above - a custom steel truss was required).

For our victorian terrace (worth ~290k) we thought it wasn't appropriate and the cash could be spent better on other things...

The extension is West facing and is being built with 3m sliding doors, 4x velux in the roof , and a high window on one of the extension walls - hopefully enough to bring light into the existing house (4m of the original rear house wall is being removed)

 

[pete1980]

Thanks both for the help, yes our house would be a similar value and we are rapidly reaching the same conclusion. We will have around 5m of bifold doors and 3x velux so as you say this should still bring in plenty of light.

drpepe - If you don't mind me asking, approximately what cost were you indicated for the gable roof / steel truss etc please? Was the 8k figure I mentioned previously in the right ball park?

 

[drpepe]

Thanks both for the help, yes our house would be a similar value and we are rapidly reaching the same conclusion. We will have around 5m of bifold doors and 3x velux so as you say this should still bring in plenty of light.

drpepe - If you don't mind me asking, approximately what cost were you indicated for the gable roof / steel truss etc please? Was the 8k figure I mentioned previously in the right ball park?

Hi

Sorry we didn't get far enough to get actual pricing, but the quote for the vaulted ceiling, velux x4, and sliding doors was enough for us to realise we didn't want to spend any more!

 

[cjard]

The mock-ups I did are below, which didn't embed in the above post for some reason. Thanks again in advance for your advice.

View media item 96761View media item 96760

The images Pete intended to post are:

//www.diynot.com/diy/media/a.96760
//www.diynot.com/diy/media/a.96761

Just in case they don't show up when Pete alters his album privacy settings so that we have access..

 

[cjard]

Pete, consider that house values for a given area will have a market average, for a particular context. People usually only go well over an average if there is something that they specifically and particularly want. If you buy a real wreck for well cheaper than the average you can add significant value by bringing it up to a modern standard at the level of finish demanded by the average, but if you throw more money at it to take it out of its price context, you really need to be taking it into another context available locally to see a return. If the feature you're adding makes it unique and weird to you then you need to find somebody else similarly weird and and also reasonable enough to see that what you've done with the place at the price you're selling appeals to their appetite for not now having to do the same..

And people are seldom that foresightful.. Take an EPC for example, if two houses on an estate were in most regards similar with regards to what can be seen, but one was an EPC A and the other was an EPC G, you'd struggle to market the A rated one for X thousands more that it really deserves based on what it saves in running costs over a long period

 

[pete1980]

Aha, thanks for the point on privacy settings for the photos, now updated!

Thanks for the input - yes we had reached a similar conclusion that it would purely be for our own enjoyment and would be unlikely to be a feature anyone would pay extra for. On balance I think we will stick to the more 'standard' lean-to roof without the gable and save the difference towards the mortgage / holiday / other unforeseen costs of the extension!

Thanks,
Pete

 

[cjard]

Dare say you'll still need something meaty to hang your bifolds off of anyway.. 3 rows of brick won't cut it as the doors will weigh far more!

That said, I prefer the plain roof. Complexities cause complications. You'd have been adding a lot more complexity with the peaked dormer thing. Chuck some velux in if you want the light..

 

[pete1980]

I'd assumed we'd need a beam across the top, with bricks at the side. Or are you referring to the sides - may we require steel supports at the side as well? (NB the pictures are a mock-up I did as a quick illustration, rather than anything from the architect, so it's not meant to indicate we will only have 3 bricks at the top!)

Presumably either way, the steel work will be simpler for the plain roof than the gable end version which I guess would need the triangular shaped steel frame if not then something stretching back to support the ridge?

Thanks,
Pete

 

[tony1851]

Option two would be a pain to build, = £££.
Aside from the structural considerations (support to the ridge; valley beams etc) the valley between the slopes may be too shallow.