Go for triple. double glazing should be a thing of the past. Triple glazing should get you closer to a u-value of 0.8 rather than the 1.3 stated, though that's with a reputable company. south facing with big windows will always be a concern with solar gain, one of the houses we done had to install a/c because it was so bad, even with triple glazing. though as you say blinds can be used! In the houses we've built in the past 6 years (how long I've been with the company) none of them have been double glazed. the science supports the use of triple glazing and be wary of any window manufacturer that tries to say otherwise.

I agree with Daisy. Use the same flooring. Anything else will clash and chop the room up too much. It will make the area look bigger and more streamline.

You have to basically cut out a hole in the wall that is as wide as two doors, then install the pocket door framework which can come in a kit form - one half then gets covered with plasterboard so that it is inside the wall, as the pocket where the door slides into when you open the door. The bit around the actual door then needs finished to whatever specification you want - usually with framing etc that a 'normal' door has. Depends on the construction of your current wall though - whether it's load-bearing and therefore you'll need some sort of beam to support the wall above. Or if it would be simpler to box out the rest of the wall rather than cut out a massive hole - in this case the room would get a bit smaller. If you are cutting a hole in a modern stud wall then it won't affect the size of the room. Door handles need to be considered carefully as you need something flat that can fit into the 'pocket' and you also need a fitting on the visible edge of the door to pull it out of the pocket again to close it.

We're currently having an extension built, builders on site preparing the footing and brickwork starting in a week or so, but I've hit a problem with our cavity walls specs. On the architect drawings (top down plans and structure cross-section) it shows 100mm facing brick, 100mm cavity, 100m blockwork (then normal plasterboard). All of the floorplan measurements are based on this size of cavity wall for the whole build. Our builder (who I have complete faith in) however says that the plans are wrong, it shuold have an additional 90mm of insulation board on all internal facing walls.... this has come as a shock as of course we agreed to the plans and had planning permission approved for what's on the plans. The new kitchen we've had planned and ordered will need to be redone, and the rooms are now 180mm (90mm each side) smaller floorspace than we were expecting. All this has only come to light right when the work is fully underway. With the plans, our architect included a "General Notes" page which includes this regarding the cavity walls: "6.0 EXTERNAL WALLS: (max 0.18W/m2k U-value) 315mm nominal cavity work, finished in facing brickwork. 100mm facing brickwork, 100mm full fill cavity insulation cavity with 90mm 'Kingspan Kooltherm K106' (0.021 W/mk) foil-backed extruded insulation to internal face (continued min 150mm below ground floor insulation level) and maintain 50mm clear cavity, 100mm Celcon Standard (0.15 Wmk) blockwork 3.5N/mm2 finished internally with 2 coat 13mm plaster." Before I contact our architect and try and find out what went wrong here, can anyone confirm whether the above tallies with what our builder is saying? I also feel as though surely the local Planning department should have picked up on this conflict. Can anyone offer advice on what options there might be to try and reduce the size of these walls? Are there thinner options available for example with the same thermal properties? This is a very standard south-facing kitchen / diner extension, really nothing fancy at all.