Is it possible to build an extension against a conservatory?

[Vacheron]

Hi everyone.

I'm hoping that some of the posters here may be able to point me in the right direction.

We bought our house in 2010 and are planning to extend the kitchen which would be simple however there is an existing conservatory (built by the previous owner) which we would rather not completely demolish as it is only about 5 years old and cost her about 20K (which we have effectively paid for in the purchase price)!

As a narrow gap down the middle would be neither attractive nor practical. Our ideal plan would therefore be to build the extension against this conservatory, carefully demolishing the adjoining side of the conservatory and replacing it with the kitchen extension wall.

Despite quite a bit of searching I haven't found anyone else with this predicament, so I thought I'd ask on here if anyone has ever done anything similar, is it possible, and what are the pitfalls?

For clarity I have attached an pic of the rear of the house and a couple of impressions of what we would like to achieve.

Thanks in advance.

Vacheron.

Current Conservatory:

Existing Conservatory

• Vacheron
• 20 Nov 2013
• 1

Proposed Extension with adjoining Wall.

Untitled

• Vacheron
• 20 Nov 2013
• 1

Untitled

• Vacheron
• 20 Nov 2013
• 1

 

[freddiemercurystwin]

There are no particular problems doing this aesthetics aside.

Yes I would look to removing that gazed wall and replacing it with the outer skin of your extension external wall joining the conservatory and extension together albeit with a cumbersome messy flashing. Or alternatively look to making the gap big enough so that you could get full access down the gap.

Also, your roof pitch looks too low if you expect to be able to tile it though can't really tell. and your chimney (why 4 pots) looks too low relative the 1st floor windows if I recall my chimney regs.

 

[tony1851]

Could you have a lean-to roof. to avoid the awkward flashing detail against the conservatory?

 

[freddiemercurystwin]

Aye would solve a multitude of issues.

 

[Vacheron]

Hi everyone. Thanks for the replies.

freddymercurystwin: Thanks very much for the feedback.

Yes, it was our intention to remove the side of the conservatory so that wall became a solid, plastered wall. The model shows them side by side for now which is misleading as you can still see the conservatory window frames against the new wall in the model.

We put a large sheet over the windows which would be removed to simulate the result from inside the conservatory and the result looks fine, nowhere near as restrictive as we feared.

The roof pitch and tiles (plus chimney) probably bear little resemblance to any building regs at the moment the roof was a quick artists impression by me to show potential ideas to the missus before we get an architect in to do all the compliant drawings.

However if the pitch needs to be increased we will run in to problems with overlapping the upper windows so that might be a show stopper for this particular approach.


tony1851: Thanks also. We started with a simple lean-to roof containing a couple of Velux windows and then looked at an orangery style glass roof. This is the third style that looked good in principle, however I have no experience of building anything of this scale and realised that things that I may think are easy could be a nightmare in reality and vice versa. So I thought it was best to ask the experts here first.

 

[tony1851]

You need a minimum 15 deg. pitch for Velux windows. If this brings the top of a lean-to roof a little above the upper cills, you can form a small 'cut-out' finished in lead under each cill to accomodate this.

That might be preferable to trying to form a flashing against the conservatory roof - one suspects you might have endless problems with that.

 

[Vacheron]

Thanks again tony1851.

I've dug out the older (unfinished) concept models from the archive. One with a lean-to roof and one with the Orangery style idea. The lean-to model shows an idea I was toying round with in keeping the windows to look between the two rooms, but I think we've abandoned that idea.

Measuring on the model, the lean-to shown has a 13.7 degree slope, however this is just set to match the model of the conservatory which may not be accurate either so I'll need to measure the conservatory accurately.
The upper window heights are accurate though, so it looks like there should be enough space for the correct slope, even if the extension was to come out a little further. (the one shown is 2.8m to match the front of the conservatory, but we could go up to 4m on permitted development, and I've heard that we can now go even further, but I very much doubt that we would need to.

(Note: The roof in my original gable idea shows as 16.8 degrees).

Sounds like the flashing / water removal is by far the largest obstacle from the sounds of it.

Lean-To

Untitled

• Vacheron
• 21 Nov 2013
• 1

"Orangery" Style

Orangery Style

• Vacheron
• 21 Nov 2013
• 1

 

[freddiemercurystwin]

You can have velux's in a flat roof you just build an upstand to sit your rooflight on or I have a feeling velux supply them now anyway.

 

[indus]

Hi everyone.

I'm hoping that some of the posters here may be able to point me in the right direction.

We bought our house in 2010 and are planning to extend the kitchen which would be simple however there is an existing conservatory (built by the previous owner) which we would rather not completely demolish as it is only about 5 years old and cost her about 20K (which we have effectively paid for in the purchase price)!

As a narrow gap down the middle would be neither attractive nor practical. Our ideal plan would therefore be to build the extension against this conservatory, carefully demolishing the adjoining side of the conservatory and replacing it with the kitchen extension wall.

Despite quite a bit of searching I haven't found anyone else with this predicament, so I thought I'd ask on here if anyone has ever done anything similar, is it possible, and what are the pitfalls?

For clarity I have attached an pic of the rear of the house and a couple of impressions of what we would like to achieve.

Thanks in advance.

Vacheron.

Current Conservatory:

Existing Conservatory

• Vacheron
• 20 Nov 2013
• 1

Proposed Extension with adjoining Wall.

Untitled

• Vacheron
• 20 Nov 2013
• 1

Untitled

• Vacheron
• 20 Nov 2013
• 1

Did that conservatory really cost £20k???