NSS

I would imagine 3 is the target for the design to meet the SAP and hence EPC, but you also need to be aware that differing APT results impact on the type of ventilation required.

If the installation is correctly calibrated then winter sunlight is rarely strong enough to trigger any tinting, but on the rare occasions that it is you can always manually override (just as you can manually tint the glass if you want to).

No problem, and I appreciate it may still not be a viable option for you, but at least you can see (literally) some of the additional benefits it offers.

View in - or rather the reflection when trying

View out - level 3 (full) tint

View out - level 2 tint

View out - Level 1 tint

View out - SageGlass clear

And as a fellow Portsmuthian you are most welcome John ?

I'll take some pics tomorrow (too late now) of the view out at various degrees of tint so you can see for yourself. The other point, and I don't know whether it's relevant in your case, but when tinted you cannot see in during the daytime. It's like looking at a black mirror from outside, which gives daytime privacy if you're overlooked or have a footpath running past your house for example.

Okay, just wanted to check they'd actually got back to you ? Can't really add much to what @Dan F has said, but don't lose sight (if you'll pardon the pun) that one of the main benefits of SageGlass is that you can still see out when fully tinted. Shame to ruin all those views with blinds imho, but it's your project and I as I said before, that's a heck of a lot of glass!

Did you have a conversation with SageGlass after I put you in touch previously?

Welcome Matt. You don't say where the plot is, but if you think similarly sized properties would be worth 1.5 to 2 million then I'd wager it will cost far more than £350k to build. You both work (and will presumably need to continue to do so to service a mortgage) so you're going to have to pay someone else to build it if you want to be in in a year. Depending on the size and spec you're probably looking at between £1,500 and £2,500 per m2 to build. Even at the low end £350k gets you something not much more than 200m2. Even in 6 acres, that would need to be somewhere VERY desirable to be worth £1.5 million plus.

30 years ago I had the gonads, I just didn't have the money. The trick is acquiring sufficient funds before you reach an age when you lack the energy or become so risk averse that yours gonads have gone into hiding. Do it before it's too late, and good luck!

By the way, I'm not suggesting SageGlass is the right solution for @tanneja, just one that he/she may not have considered. Our requirements were unusual due to the need to avoid having to night purge making SageGlass the perfect (if expensive) solution in our case.

Fair enough, but the OP has 17m2 of south-facing glass so I don't imagine getting a good amount of winter solar gain or good light transmitting will be an issue regardless of the glass type.

But again, if you have lots if glass then the need for a high percentage light transmittance is less of a problem.

Why would you see that as an issue in a well insulated, low energy house? Bear in mind I live on the South Coast not the frozen wastelands north of Winchester ?

But I'm not talking about Solar glass, but SageGlass and when not tinted you'd be hard pressed to see any difference in the view out between it and ordinary glass. Edited to add pic. Full tint (96% of Solar Gain blocked) v clear.

Nope, you can still see out clearly, just through a tint.

Okay, but blinds will also make it darker inside, surely, and when closed you can't even see out of the windows.

Yes, it works very well for us, though we have nothing like your 17m2 of South-facing glass. For us it was the most apt and elegant solution but, as you'll have read, it comes at a cost. We were very fortunate as the first UK residential site to get a hefty discount. If we'd had to pay the full price we'd probably still have done so and almost 3 years of use has only made me more convinced it was the best solution for our particular situation.

Bear in mind that solar gain may be your enemy in summer (perhaps more so in late spring and early autumn), but your friend in winter. Any fixed or film coating will not recognise that.

Looks like a ridge tile?

?