Ralph

HI, not that far really, just by Brechin

Thanks guys, appreciate all the help.

@Declan52 Most of the builders round here don't have great things to say about ASHP, I assume it's because they have been poorly specified. A lot seem to be saying the weather here is not suitable, too cold or changeable. I hear some are starting to fit a hybrid ASHP that has small oil burner backup.

Hi @Simplysimon, Yeah the glass is coming back to bite us slightly. I wonder how much weight 3g would add and would it impact the structural elements, probably not. I'll have a look at pvc, thanks for the advice.

Hi Peter, The windows are supposedly pretty decent quality by Nordan although admittedly 2g. I've attached some plans and I would be delighted if anyone wants to take a look. You've all been very helpful. Regards Ralph2016 AHI 05 Plans Elevs.pdf

The only air values I see are Air permeability at 50 pascals: 5.00 (design value) We were going to use Scotframe Val-U-Therm pacakge which has a certified 0.13 U-Value for the walls . It needed quite a bit upfront so we went with a built on site option which I being told has to be calculated with Scottish Accredited Details which results in poorer u-values.

Hi Declan, Kw We're pretty rural so no gas. We could do oil but I'm being told that would require a 4KW of PV cells to offset the C02 (Scotland has different regulations from elsewhere) As they would have to be ground mounted it will take up a load of room and be expensive. Excuse my ignorance here but by openings does that mean external doors and windows? The windows we are looking at are 1.3 although there are a lot of them.

Sorry, still trying to get my head round the 48 pages of calcs I've been given, ---------------------------------------------------------------------- 2 Fabric U-values Element Average Highest External wall 0.22 (max. 0.22) 0.22 (max. 0.70) OK Floor 0.17 (max. 0.18) 0.17 (max. 0.70) OK Roof 0.12 (max. 0.15) 0.14 (max. 0.35) OK Openings 1.40 (max. 1.60) 1.40 (max. 3.30) OK ----------------------------------------------------------------------

The Energy Efficiency Rating is 82 and the Environmental Impact (C02) Rating is 82 with the ASHP and 96 with Biomass

Hi Peter, yeah the insulation is good and I'd be happy to increase it if it would mean no PV. To be clear I don't have any issue with installing green energy at all. I'm just trying to get the build cost down. I'm not sold on biomass though, it seems expensive and to be honest overkill for a house our size. I also think the green credentials are suspect.

That is the size that comes back on the SAP calcs, I'm assuming it's the minimum required to meet the regulations. It makes me wonder if there is something else we can do to offset it and void the PV all together? As you say not worth bothering with if it's all you're going to do.

Hi all, We’re struggling a bit to come down on a choice of green energy for our new build in north east Scotland. According to our SAP calcs to meet the Scottish government C02 regulations we’re looking at either: A biomass boiler with 0.5 KWp PV on a ground array (roof is too flat) An ASHP (Mitsubishi Ecodan 8.5kW is being recommended) again with PV on a ground array We’re not self-builders it will be a main contractor. We’re trying to keep the build cost down as low as possible. To be honest I would have been happy putting in an oil boiler with radiators instead of underfloor but that would require something like 4 KWp. A pretty big ground array and quite expensive. I’m leaning to the ASHP plus PV but any comments would be welcome. The house is 2 story, about 200sqm with a fair amount of glass. Thanks in advance.