Mike

Calculation is complicated because each material responds differently at different frequency ranges. The simplest solution is to look at manufacturers technical literature, where they will have a number of standard constructions already calculated, and choose one of those. That's a good design from the fixing and the airborne sound perspective. If you're concerned about impact sound then you may also want to use a separate frame for each side of the partition (particularly for a kitchen or bathroom next to a bedroom) - or arrange your rooms so that you have a built-in wardrobe on one side.

On balance I'd imagine that it would be a plus to keep the MVHR unit running to provide some measure of smoke extraction during the evacuation. But it would be interesting to read something from a fire safety engineer.

Soraa LED Vivid are the best I know, but aren't cheap - for example https://theledspecialist.co.uk/search/?q=soraa+vivid Personally I'll probably be choosing Tridonic modules (or similar) on my upcoming project in lieu of GU10s - see this discussion:

This. Layering different types of lighting - ceiling lamps, wall lamps, spot lights, table lamps, floor lamps, etc. - to provide a variety of light intensities and suit different purposes. Take a look at some of these : https://duckduckgo.com/?q=ambient%2C+task%2C+accent+lighting It's best to stick with one colour temperature per room. In other words if you like warm lighting in a bedroom, stick to 2700K. If you don't know what temperature lighting you like, you can always buy a few bulbs and test them out.

I'm one of them! For a modern home 4000K is perfect for me in all rooms - a good balance between too warm and too cold that doesn't overly distort colours. I know that many people like warmer in bedrooms & living-rooms, but personally I'd only do that if I lived in a 'heritage' building, had wood panelling, or similar. I'd only go higher if I wanted to deliberately enhance the whiteness of a room (I once used 6000K to brighten up some dingy white-painted subterranean corridors previously lit with something like 2700K). Because mixing colour temperatures looks strange and unplanned (unless you plan to have them on at separate times, not simultaneously). Other tips: Do go for layering - ambient, task & accent lighting. Ambient lighting doesn't have to mean downlighters in regular grids in every room; that produces even but bland light. They're usually better when used to wash curtains or walls, mixed with narrower-beam spots directed at tables, shelves, etc. Do use dimmers on the ambient lighting in bedrooms & living rooms. Do look at the colour rendering index (CRI) of the light source - a higher rating shows objects closer to their 'real' colours (<80 poor, >90 great).

Undoubtedly the best solution where feasible.

There is another product on the market - or rather two products, once for cooling, the other for humidifying - specifically designed for MVHR use, from HomEvap. As noted above, the low airflow in MVHR systems means that the effect will be modest, though so will the cost of running it. The cooler works by humidifying the extract air just before the heat exchanger, dropping the temperature through evaporation, which then cools the incoming air by a few degrees, with no need for a separate chiller unit. I'm hoping to install one later this year. The humidifier is fitted on the supply side. In the UK you can buy a Blauberg branded version of the cooler, albeit at a premium price. They may sell you the humidifier too, otherwise you'll need to find an EU supplier prepared to ship them to the UK.

I did the same several years ago too - currently using my UK local code on my mobile phone in France via Voipfone.

I still have a Zanuzzi bought one in the late 1980s. I've replaced the pump and the door lock, but other than that it's still OK - though I do plan to replace it later this year.

I've occasionally come across similar shortened baths with built-in seats in France. They're never deep enough to use the seat, and the seat gets in the way to use it as a bath - so they only work as weird looking shower trays. OK for kids, I guess, but otherwise I'd avoid except for the deep luxury versions.

And, because you'll need to apply a good amount of force, be sure to wear eye protection in case you break the bit.

Yes, but only for units independently assessed for the Passivhaus Institute: https://database.passivehouse.com/en/components/list/ventilation_small However, as @JohnMo says, your previous experience could also have been due to other factors.

It's not only the positioning on the ceiling that may get noticed. Depending on the fitting and the beam angle, the light cone / shadow cast on the wall may also look misaligned.

Well my knowledge of BS EN 12380 : 2002 has improved. Valves rated Class A can indeed be installed below the flood level. However it looks like they're only tested under a 1m head of water - presumably a static head. BBA certificates are the gold standard - with one of those you should be able to convince Building Control, provided you install it according to the Certificate. But the BBA search seems to be down and I can't spot one elsewhere for the Ventapipe valves. However I do have one for Durgo (BBA certificate 06/4325), which states that the '82 mm and 110 mm valves are for use on discharge stacks serving up to 10 storeys' subject to a maximum flow rate of 37.1 litres/second. Their 82mm valve is A1 rated, so could be used below the flood level; the 110mm one that is normally be used is Class B, so couldn't be. You'd need a 110 to 82mm adaptor, and it would need to be on the soil stack. That might give you some extra flexibility. However I've seen AAVs that have leaked foul air into a room, so although I might be tempted to use one below basin spill-over level, I wouldn't below the spillover level of a WC!

I used to have an IR ceiling heater in a bathroom - it didn't last long. The problem with IR is that it provides line-of-sight heating - it will warm only the side of you facing it. Central heating, especially UFCH, is vastly superior.

This gets my vote too - better to be deliberately off-centre than maybe-not-quite-centred. If you decide against that, then what is the lighting doing in the rooms on either side of the doorway? You may need to consider the alignment of the lights between all 3 spaces.

If you have a WC, you need this (the height just needs to be higher than the highest bathroom fitting, so potentially a bit less than 200mm - check the AAV instructions). A small AAV on the sink is only protecting the trap in the sink waste.

Just a guess, but I'm hoping to save between 1/3 and 1/2 of the labour cost and, by carefully shopping around, maybe 10% on the materials. But I won't have an answer for a few months.

I can't comment on the lock price, but I always choose laminated glass over toughened for it's resistance, and it's UV-blocking ability (to prevent furnishings fading).

I recently had a similar quite for a 1 bed apartment - albeit it's well specced. So I'll be doing all the prep - putting in all the ducting, wall boxes etc. - and buying almost all the kit, other than the cables, so the electrician only has to pull the wires through, fit the consumer unit and make the connections, similar to a rewire. Although you still need to know what you're doing to get everything in the right places.

I don't use a bath, but in winter I like my showers at 42°C. Cooler in the summer.

+1 A flexi is that last thing I'd use anywhere. I've changed too many burst ones in the past.

It depends on your objectives and in what way are you think it may be overkill. FWIW I'm planning to install a Zehnder ComfoAir200 in a 40m² apartment, which you could call overkill. However it's suitable for several reasons: I can minimise noise by keeping the fans pretty slow under all normal conditions, it's one of the best performing units that I can fit in the limited space available, and I need a good intelligent summer bypass. Plus, by shopping around, I can get it for an acceptable price. I'll be feeding it with 125mm ducts - you don't have to use 160mm with Zehnder if you don't need the extra airflow. You can find independently evaluated performance figures for the Zehnder unit in the Passihaus List. You can't do a you can't do a direct comparison with the Vent-Axia unit; they haven't had units evaluated so as you're reliant on their own figures.

You can't do that in Example 1.4B above either, so no.

I think that's your solution. No doubt a sparky will be along to confirm.