Kelvin

Have you paid all of it?

You’re right. Builders are wrong. They either know they are wrong and fobbing you off or they don’t understand how insulation works.

The public don’t care about that. Remember when Top Gear used to tell you how big the boot was. Now they blow up caravans.

I’ve had this as well. Both from a it will be cold angle and it will blow down in the wind and they then reference the granite and sandstone old Scottish houses with their big thick walls. Just at Christmas i was in such a house where this comment was made. They had the oil boiler on running nearly all day and a stove in the evenings. They also used electric space heaters in some of the rooms. They commented how warm their house was. I didn’t get into a discussion about it but these were smart people who just don’t understand how buildings work at a basic level.

If it’s warm to the touch then your flow temp is probably too high. Think of the slab as a massive radiator therefore it doesn’t need to get that warm to heat the room up. It just does it slowly. Also floor tiles are a good floor covering for UFH. Carpet is the worst as it acts like an insulator.

There are several very expensive houses on the Islands. I’ve been in one that cost similar money. Me being me I knocked on their door to tell them their house was stunning and they invited me to look round it 😂

Your pump is the same spec I had in the last house. Now I don’t know the loop sizes etc as it was all done when we bought the house but it was a fairly large house with a big ground floor. Therefore it’s unlikely to be your pump. That said we did have two separate manifolds each with their own pump running at speed setting 1. Our mixer valve wasn’t set to max either.

They do indeed. We had a shared holding tank and pumping station at the previous house that pumped the sewerage to the main sewer pipe at the bottom of the drive which was a few hundred metres to the road. If had two pumps in a float chamber. It was oversized for the 8 properties and consequently would get a bit stuck occasionally largely because the wrong things were getting flushed down the loos. You could manually activate the pumps rather than wait for it to automatically pump when it was full enough. Sometimes though you needed a big stick. 🤮

Performance details https://erpfichetool.jouleiot.com/#/specification/Joule UK/HMMC-PP-012

What is the ultimate benefit of it given the cost and apparent complexity?

Plant room envy. 😂

I’d say your numbers are skewed a bit by ProDave’s as he never used all of it and the plant is split between spaces and nod’s (12.5mx1.2m ? ) We sacrificed a bit of width (500mm) to widen the hall as otherwise would have been a bit long and narrow. I looked at taking some space from the utility room and moving the hallway down a bit but it would have meant re-doing the drawings and adjusting the steels so it will have to do.

Read as much as you can. Look at YouTube. Go onto the barrier manufacturer websites and look at their info. Many of them do CPDs so join them.

Airtightness. Half day. Bit of theory bit of selling to you, some demos, then some practicals on applying the tapes and various solutions for penetrations.

Very detailed in theory but in practice it just needs careful thinking about how air could move in and out of the building and then careful detailing. The hardest bits are awkward junctions, where different materials comes together, making sure no unplanned penetrations are made in the barrier and if they are they are highlighted and fixed, no boxing in or covering up anything until you’ve checked it and had a preliminary airtightness test done. Your drawings should have a section with a red line around it showing where the airtight barrier is and your construction drawings should have a section on each main component of the house showing the detailing of the junctions for all the components including the airtight barrier. I did a practical course at the NSBRC which was useful.

From memory you have a relatively small output ASHP?

Lots of RPi fans on here. I had several dotted round the last place doing much the same plus music streaming and an arcade machine. The issue I found was it’s not house friendly with the people that also live with me. When it inevitably fell over and I was away I’d get a load of white noise. Consequently I’m only allowed to put HA into the new house if it’s a ‘proper system’ and not some ‘hacked together bag of shit you’re always tinkering with’. In other words it needs to be invisible from the biologicals.

Exactly. 99% of buyers will have no idea what a passive house is. Many will now care a bit more about how much it costs to run so sticking the utility bills under their nose will be a good selling point. I can see old draughty expensive to run houses becoming harder to sell if energy costs and interest rates remain high.

He was a bit vague but the summary seemed to be their calcs weren’t detailed enough when considering all the various factors. This seemed counter intuitive to me on why it would subsequently push them to recommend the next size of heat pump for every install. I don’t know the typical house they are installing them in so it could be cold houses.

That was the impression I got from them too.

UFH in screed with 200mm insulation. No rads upstairs we’ll wire for electric panels and then decide after a winter if we need them. 40oC albeit we’ll run it lower. There’s only two of us most of the time so hot water demand isn’t great.

We had a comprehensive SAP report done and from this the timber kit company had a report produced with recommendations. The SAP report was based on the as designed at the time but since then I’ve improved the floor insulation and gone with 3G instead of 2G throughout. It also assumed an as designed air change of 3.0 where my aim is to get under 1.0. I also plugged the numbers into Jeremy’s spreadsheet and the total heat loss in the worst scenario is 3.6kW which more or less tallies with the detailed SAP report. Consequently the ME guys recommended a minimum size ASHP of 6.8kW so we specced an 8.5kW Ecodan and this is what the installer also recommended. However the installer emailed me today and said that they’ve reviewed how they do their calcs after feedback they received and it means they now recommend we go to the next size Ecodan up so 11kW, the difference in price is only a few hundred quid. I called the ME guy that did our report and he said that doesn’t make any sense to him and recommends we stick to the 8.5kW. I’ve got a copy of the spreadsheet the installer uses so will plug our figures into that and see what it says but my expectation is it will match what I already have.

What is the advantage of getting certified anyway? I assume it costs money to do so. I’d have though that near passiv gets you 99% of the benefit without the apparent hassle and complication.

Our barn style is room in roof 1.5 storey with a large (16m x 4m) single storey porch attached to it.

If he fancies a holiday in sunny Perthshire 😂