CADjockey

Yup get that, I just wanted to understand how it works and it gives me some peace of mind to feel it's not just a load of smoke. I will be requesting a full calcs sheet in any event.

I'm sure they can, but thanks.

Hi, further to recent post on window combined U values, I've investigated the maths to make my own calculations and it's reasonably comprehensible. I followed a short YouTube video and now have an easy to complete spreadsheet that will do the heavy lifting. The only hole I have is an understanding of how to calculate the Thermal Bridge Coefficient for the final multiplication for which they used a 0.3 value... If anyone has a guide or can tell me if 0.3 is a usable figure it would be most helpful. I'm sure the window manufacturers/suppliers can and have done all this but the fitter seems less knowledgable and as I need to be able to provide the evidence to the SAP guy in th end I thought a little knowledge would not be a bad thing. Many Thanks.

In this room specifically, north facing and tree shaded, never gets overheated on this side of the house. Apart from that we are adding in a 'reverse' function to the GSHP to push excess heat back into the ground in the summer months if required, especially if the summers are going to get warmer in future!

I might add at this point that we are replacing a house that was entirely of wooden construction (1950s), 150mm thick (empty) walls with no insulation, single glazing and even cedar shingle roof tiles. So in some ways, what we are building will be at least twice+ as insulated. If the GSHP, UFH and MVHR do their jobs we will be more likely to be complaining about solar gain from the south facing bifolds 😅 That said I am looking into better as I type...

Yeah, point taken. But they don't advertise them as shed windows do they?

They are frame profiles from ALUK, local supplier. I may change the tiny window to a fixed unit and reduce the frame profile by half. MVHR will mean we don't need to open the window really anyway.

I've put the order on hold until I get some sense. It seems slightly incomprehensible how they can potentially manufacture and sell something that is not to the required legal spec. Projected EPC is a high level B, but that was with windows that only the Scandanavians can make as far as I can tell.

Afternoon, I could do with some help if you brains out there might be willing. I've got a newbuild underway, there are a raft of windows and a couple of bifolds, all in aluminium. and have just been informed that the whole house windos U value is calculating at 1.7. I gather the 2023 Part L requires 1.6 min ( or max if you like) but I don't know what the previous part L required to know if I'm in regs or not, I just can't find the prior documentation. We commenced building May 2022. Add to this picture the fact we are currently installing an MVHR system so will have no holes in the windows for the heat to leak out unfettered (trickle vents). Do I need to meet 1.6 legally or can you offset against the whole fabric of the building with the additional insulation under the floor screed or in the loft for example? Help!

Installed the two boreholes of 108m each, and have committed to UFH & GSHP system with MVHR for fresh air distribution. However, given this summer and the future that we are all being told is going to see more of that, I asked our system provider & fitter about reversing the system to cool the house, or such the warm out of the slab. I need an additional bit of kit as far as I grasp it, but he tells us that it can put the heat back into the ground. The slightly astounding bit is that the heat doesn't dissipate but hangs around to some degree until you switch to forward operation in the autumn and pull it back out of the ground again. Anyone got any exsperience of running in reverse for cooling a GSHP system? A bit of a longshot maybe, but you guys are a font of interesting information 🤣

This seems like the simplest bit we are installing what with the GSHP & MVHR ! They call it recycling but yes I think it means recirculating the header tank. https://www.rainwaterharvesting.co.uk/product/rain-director/

It's filtered before it goes into the tank, and I think it's filtered before it's pumped to the header tank. Therafter it's only used in the, garden, toilets and the washing machine. The system control provides for recycling to prevent stagnation in the header tank, but it's not being used where mains quality water is required (taps & showers).

Got a Brinno, set up from 8am to 4pm at five minute intervals. Batteries last a good month. Here's a typical recording... but I did discover that I'd left the protective film on the waterproof case, doh! So am expecting the latest output to be better. TLC00035_JUL22_ 27.mp4

By Michael Jacksons ex bodyguard if the tabloids are to be believed, who is going to turn it into flats!

Just installed a 7500L tank for toilet flushing, washing machine and watering the garden. Calculations tell me that our usage could be ~71kL and the capture could be ~62kL. Currently not on a water meter, but should significantly reduce our fresh water requirement, and thgeoretically provide 38 days of drought resistance.