ProDave

Didn't we have a thread on this recently?

It might be the Windy city, but they would certainly have to work over a very much wider seasonal temperature range than UK housing.

Interesting read, I have not yet fully digested it. but a few initial thoughts. Most of the houses tested are >10 years old, hardly cutting edge, and only a few have MVHR. There is a clear conclusion that passive or trickle ventilation is not adequate, and the houses with mvhr perform better. There is the strange observation that most bedrooms are overheated and the notion of wanting a cool bedroom is unachievable in a well insulated air tight house, which is strange because we have been managing this since our house was built. There really is merit in not heating the upstairs at all if a cool bedroom is your requirement.

It really is simple. Work out how much your required fall falls in 1 metre. Make a spacer of that amount and tape it to one end of a 1 metre level. Then you set all the pipes level with the bubble. What can be so difficult?

I keep on saying it but the proper old fashioned mechanical thermostats when wired properly with a neutral connection for the accelerator heater work damned well. But it is harder now to find the proper ones. If they don't "click" as you turn them up and down when not connected they are electronic imitations.

I would try some tape. Something like Frog tape is sticky to try sealing it for a test but will peel off with no residue. If sealing inside makes no difference try sealing outside, though you don't really want to be up a ladder when it is blowing a hoolie.

Yes in normal use DHW would start re heating when it goes a few degrees below it's set temperature. So a normal reheat is easily done in it's half hour window. But Daughter likes to shower until the water goes cold. I just can't get through to her you are not going to come out any cleaner after a half hour shower than you would after a 15 minute shower. So when she is done, most of the 300L in the tank will have been displaced by 6 degree incoming mains. Allowing for mixing with the small residual tepid water that was left in the tank, I have seen the temperature sensor starting at 9 degrees when starting a re heat from that.

A bit slow. I can't accurately define how slow but I am sure someone will do the sums and tell us how long it should take to heat 300L of water from 6 degrees (yes that is the mains water temperature at this time of year here) up to 48 degrees at 5kW heat input. Most (if not all?) heat pumps set time limits on how long it will spend heating DHW before reverting to space heating (they never do both at the same time) I have mine set at the moment for 30 minutes heating DHW then 30 minutes heating the house. So whatever is the theoretical heat up time, double it with my present set up. I could set it to spend much longer heating the DHW, with a near passive house you don't have to worry about the house going cold if the heating input to the house stops while it is heating the DHW.

Pictures of the window from the outside both close up at the details and a zoomed out view to give overall context please. We had a similar noise at our last house, though lower frequency. I believe it to be nothing to do with the window but a seam in a Tyvec layer around the timber frame not taped properly, and able to blow like a reed and make that noise at the seam.

Many on here including myself will confirm a near passive house building will work perfectly well just with UFH downstairs and a small ASHP. My 5kW ASHP works fine even over here on the east where I am sure it is colder than Ayrshire.

Re mvhr "evening out" temperature. When we light the WBS, we tend to put the MVHR onto the medium boost speed for a couple of hours in an attempt to spread some of the heat around just a little and it does seem to work, it can easily lift the temperature in the non heated rooms a degree or sometimes more in an evening.

I suspect what it will do, is at temperatures close to the dew point, is increase icing up as the recirculated air will be colder, and increase defrosting frequency, and hence reduce efficiency that way. I still favour rotating the unit 90 degrees so the cold air gets blown past your door not across to your neigbour.

FAR more important than size, is the type. We once made a gravel area with 20mm stones, but they were all rounded stones and they just rolled on each other, bad enough to walk on, hopeless te drive on. Whatever you get make sure they are crushed or irregular shaped stone.

This is the you tube vid about guys deliberately boxing in a heat pump and watching the air flow with a smoke candle.

I assume the open door in the picture is yours? Rotate the ASHP 90 degrees so it blows along the passage not across it. It would blow the cold air past your front door not your neighbours. Putting screens in front of them is very bad, on another thread recently someone posted a you tube clip of an experiment to box one in, and it ended up recirculating it's own air and choking itself.

It was at the time Kingspan had a little forray into the market and had re badged the Misubishi Lossnay units. They had abandoned that idea and the Kingspan units were coming up on ebay. I think i paid £400 for the unit and £100 to get it delivered.

How much are CO2 meters now? I remember looking when they first became mandatory (we missed that requirement for ours) and thought HOW MUCH?

My recollection of school classrooms is at change of period when you all march to the next classroom previously occupied by the last lot, the air in the room as you walked in was rank, and all the windows were thrown open to make it breathable. You tend not to notice the stink and lack of oxygen when it is you creating it and it creeps up gradually. Scottish regs now demand a CO2 meter in the master bedroom. If they were not so expensive I would buy one out of curiosity, as a measure of how well the mvhr is actually doing.

I find that a staggering cost. My mvhr unit was about £500 and all the ducting about £1000 all DIY fitted. Even allowing for doubling due to inflation I don't see where £10K comes from.

BUT in Scotland if your air test is better than 3, you MUST fit mvhr. One self builder near me wanted just to use MEV ventilation but was "disappointed" his air test was so good and BC forced him to fit mvhr. It was a pig od a job as much of the plasterboarding was done so he ended up with 2 small mvhr units one upstairs, one downstairs. Far better to plan for good air tightness and mvhr. If you really really don't want it, build in some deliberate leak to give a poor air tightness test, a leak that you can then "correct" after the test has been done.

The only time I have seen a chimney rendered like that (though usually at least smooth!!!!!) is following damage from a chimney fire. Is the foam just a crude attempt at blocking air and possibly smells coming through from stinky neighbours?

We found Sutherlands would transport a static they sold for free, but the distance was less. Completely different matter if you want to buy one privately and just want them to transport it. On our first build when we came to sell the static at the end of the build, the buyer ended up getting someone almost from Aberdeen to transport it as the local people just were not interested. This time I arranged the planning so it does not ever have to leave our site, it remains with PP as a garden outbuilding (not for habitational use) You would not get such a large garden shed for the money.

Normally you would apply for temporary planning for a static 'van with your planning, but I believe crofting law allows 3 caravans on the croft so I doubt you need to bother. GNR Sutherland at Edderton is the local caravan dealer and they always have a selection from posh to basket case. Next time you are passing up / down the A9 turn off at the Dornoch Bridge roundabout for the short detour to take a look.

Hi and welcome. Another Highlander here just north of Inverness. You are in good company. Dare I say if for getting a reputation, but how about selling the house and moving into a static caravan on the croft? WAY better if you can avoid borrowing and the hoops that makes you jump through.

I remember cladding our sun room, a major part of the planning was setting the spacing between boards to work, meaning a different spacing on different walls, a bit like gauging a roof so a whole number of tiles fits the gap. And I wanted to get a common detail around each window so an outer board comes up to the corner. I painted all mine because I don't like the weathered "old wet shed" look. One coat before fitting and one coat after fitting. In this case the windows outer edge was only slightly back from the inner surface of the timber so just a small filler was used around each window and the outer boards overlapping over this filler. Above the windows the bottom edge of the board was cut at an angle to make a natural drip bead at the outer edge.