Building a house

[Mayoffs]

I'm getting a substantial overhaul on a 70s semi-D. New bathroom, kitchen, complete heating system, rewiring and extra plugs etc, interior warmboard on external walls. Basically a lot of ripping at the same time. Any observations on extra things to do or things to watch out for welcome.

Hello Armaghniac, just to add if your going with what looks like a substantial renovation, it would be worth it to also add good quality attic insulation and windows, if applicable. Watch out for any legacy plumbing in the attic, after upgrading the insulation it may be vunerable to low temperature conditions so make sure to add a heat lamp / heater and thermostat. Also, no harm carrying out a radon test if your area is susceptible.
Good idea insulating the exterior walls, you will see a huge difference in your home, especially during cold, wet, humid conditions.

[Mayoffs]

Just noticed the date of your post, job must be done by now !

[armaghniac]

Just noticed the date of your post, job must be done by now !

Thanks Mayoffs, the work has still to proceed.
The windows are recent, I had to attend to them to avoid freezing altogether.

I will be replacing the tank in the attic and will be concerned about insulation.
Does there exist frost valves that would stop the flow in artic conditions?

[Mayoffs]

Yes, frost valves do exist and are usually installed as part of a solar panel installation. They basically discharge water in a section of line if it gets cold enough, internal stat stops the discharge once a specific temperature is reached. That's one type anyway. Pros and cons to both set ups, you could ask around the trade for other opinions. Best of luck with it.

[giveherlong]

Anyone ever use the drimaster system for ventilation? Pros and cons over heat recovery?

[Hereiam]

Drimaster is not a substitute for a heat recovery system all it does is  elimate the need for trickle vents on the windows. It is a PIV unit so it takes the air from the attic and blows it into the house there is no heat exchanger with this put you can get one that heats the air coming in but this uses a built in heating element. The theroy is that it keeps the air in the house moving so condensation is never a problem.

[illdecide]

A great job altogether, you can get ones with just normal room temp air or ones heated with an element a stated Hereiam stated, if you have any damp or major condensation these are fantastic for eliminating this. They are quiet and prob only need to use them from Nov - March, would def recommend.

[giveherlong]

Thanks lads
Think they may rule out the need to have fans in each bathroom for building control regs?

[Hereiam]

No GHL you will still need the extract fans if you put in a drimaster which cost about £100-300 whereas a heat recovery will set u back 3-4k but this it is with this that you do don't put the standard extract out through the walls.

[illdecide]

Thanks lads
Think they may rule out the need to have fans in each bathroom for building control regs?

They are one of the most important things in your house, some stupid people actually have them installed but have them turned off...Pay a bit extra and get the more powerful extractor fans put in (not sure of the l/sec but it's prob about 60 - 80 l/sec)

[redzone]

Is it important to have the dri master turned on in a new build. Would it make that much difference

[LeoMc]

Is it important to have the dri master turned on in a new build. Would it make that much difference

A new house will have fewer exit points for moisture soi would have thought it just as important.

[Hereiam]

Turn it on and dont turn it off. Mine goes 24/7 of course it automatically turns of when the roof space gets hot in the summer and cold in the winter.

[giveherlong]

Any views on cavity insulation, pumped in bead Vs built in?
I'm thinking of going with the bead- what cavity size would you go for?

[Hereiam]

150 cavity with 100mm PIR Insulation. Not a fan of the blow in stuff as u are relying on someones word which these days means nothing