Russdl

Good point. Ours provide plenty of privacy by day - you can’t see in at all - but by night (when they’re usually up anyway) they may as well not be there. A bit like the net curtains of old.

😃 I wish!! But they do work well on smaller hoses as well.

Clearly the best and easiest solution if you have the space to do it, and you can do it without killing the PV at the same time.

I think you'll find you're right 👍

And in case anyone is interested in the blinds, it's these.

It's Warmcel

We learnt how to keep our house cool this summer and thought we'd share what we've learnt in case its of use to others. We're in a timber frame building built to the Passivhaus standard but not certified. We don't have an ASHP, so no slab cooling for us but without a doubt our (not so secret) weapon are the external blinds. All our east and south facing windows (with the exception of 3 east facing windows - more on them later) have external blinds and as predicted by the PHPP these are the game changer. Our secret weapon is the little personal weather station (PWS) in the garden and with it's help this is how we've kept the house cool: In the evening when the outside temperature according to the PWS is below our target internal temperature of 21 degrees all doors and windows are opened and the MVHR ramped up. Overnight all the inward tilting windows are left open with the MVHR staying at a higher level and it stays like this until the PWS shows that the external temperature is rising towards our target 21 degrees - that happened at 07:50 this morning. As soon as the exterior temperature reaches our target then all doors and windows are closed and the MVHR is reduced to its lowest setting, we monitor the air quality with a couple of CO2 monitors as recommended by @Adrian Walker and increase the MVHR speed as required to keep good air quality. All sun facing windows have the blinds down, we have the mesh style blinds that don't block off the light but stop lots of UV. With this technique our hallway temperature has peaked in the early evening at around 21-22 degrees and the kitchen/dining room which has lots of east and south facing glazing has stayed below 24 degrees. As soon as we open up we get rid of most of that unwanted heat. The hallway starts in the mornings around 19-20 degrees. The reason I think the PWS is a secret weapon is as far as I'm concerned you need to accurately know the exterior temperature and when to let it in and when to keep it out. On a windy day, 26 degrees can feel cooler than 21 degrees but if you let that stuff in the house you're gonna regret it. If you don't have a PWS you'll probably be able to find one situated close to you on the Weather Underground website. Oh, and the 3 problem east facing windows without external blinds: 1 is the utility room. That has an internal blind and as it's the utility room the internal door to the rest of the house is kept closed. That room gets warm 25-27 degrees but the heat stays in that room which of course has an MVHR extract so the heat is slowly being pumped out of the house until it's door/window opening time then we throw the heat away with vigour. 2 is the ensuite which we deal with in exactly the same way as the utility. 3 is the main bedroom which has a great big window and curtains. The curtains remain closed while the sun is coming in that window but the doors are open so as that room warms up its heat is not being contained in that room. As the sun moves round and that window is no longer in direct sun the curtains are opened and a big old chunk of hot air falls out to be slowly extracted until window opening time. To me, its like the house taking a long overnight gulp of cold air and then holds its breath throughout the day until the temperature is 'just right' again.

Anything but (in our case at least). Right now nearly every window is tilted open and will stay that way until morning whilst the house takes a big long breath of cool air. In the morning when the outside temperature gets to that of the inside temperature then everything will be closed up and the house will keep its cool until tomorrow night when we will rinse and repeat. We also turn the MVHR down to its lowest setting when it’s properly hot so that it’s not breathing in more hot air than absolutely necessary. It’s worked a treat - no overheating at all.

We have a recirculating extractor which vents down by the kick board a few feet away from the hob (after going through grease and charcoal filters) in line with an MVHR vent in the ceiling above. The extractor does its own thing regarding speeds, run on time etc. We never boost the MVHR. It all works very well.

That’s got to be a ‘no’. Down-lights do highlight the imperfections but that is extreme to put it mildly. An expert will be along soon to help, I’m sure.

Have you looked at wood plastic composite cladding (WPC)? It’s reassuringly expensive but won’t change colour apart from fading a bit over the years. We’ve used the dark grey which has moved a bit in this recent heat on the eastern elevation, aside from that we’re very happy with it. Here’s a screen grab from the envirobuild website, other WPC is available.

It used to be that you had to be on the Agile Incoming Tariff to get the ‘Outgoing’ tariff. Has that changed? The half hourly changing Incoming Tariff can be brutal, I was on it over the last winter (when, of course, there was very little ‘outgoing’)

I had too much time on my hands, so I watched the video. Utterly brilliant.

Ah. Got it. 👍

There is no FIT anymore. If you have the space for more PV I’d say “go for it” regardless of what other decisions you make.

Afternoon all. Does anyone know where I can get these standing seam roof clamps from individually (or something similar)? I've found them on Amazon, £55 for 5. I only want twenty quids worth!

As above. I used Osmo oil with a grey tint. They still look the same - haven’t gone orange and no one’s come a cropper yet.

@Thorfun I had similar concerns and ended up making a ‘pre filter’ box between the vent and the MVHR unit. I used a pair of tights as the filter material, works a treat. If you’ve got the space/time it may be worth a go.

I’ve no idea how robust those seams are, but it has to be wrong for the points you’ve raised? Hopefully an expert will be along soon to confirm or dispel your concerns.

Really interesting that you mention that. Over the last hot spell we saw a difference of 9 degrees for exactly the reasons you’ve explained, but why is our temperature difference so much larger than yours? We have an enthalpy heat exchanger, does that make the difference or are we just lucky?!?

We demolished a bungalow and then rotated the new build through 90 degrees to optimise solar gain and solar PV orientation. This was all explained in the Design and Access Statement highlighting the environmental benefits of the change of orientation. We are 90 degrees out of orientation with the houses that surround us but as we’re down the end of a track and there is no street scene as such the change of orientation wasn’t mentioned once by the planners (but hundreds of times by people wandering past!)

You are clearly in the wrong place.

If you have a bit of spare time use Sketchup. It’s not that tricky when you get into it. YouTube will help. Model the shed with standard sized OSB, ply or whatever you plan to use.

Interesting. Any idea why that would be?

Quite some difference there, how does that work? Some are good, some are brilliant? Got to say the plasterers we had were definitely brilliant and way less than £200 a day, but that that was around 2 years ago and times have definitely changed in those 2 short years!!