Alan Ambrose

Look at annular cutters - the go to brand is Rotabroach. I would rent a mag drill if you’ve got more than a couple to do. You need a slow speed, cutting fluid, to clear the chips out regularly (e.g. with compressed air) and to control the drill pressure. The forces are high so be careful as others have said.

I think UKPN have a spec somewhere, concrete base etc - ask them. But this kind of thing: https://www.ebay.co.uk/itm/193232069236 not necessarily that size though. One option is to keep the meter in there for ever.

Thanks, some interesting insight. Clever to make the North facade the most glazed. I was surprised that you had to increase the size of the windows, my feeling (I have not done the ventilation calcs yet) was that I would be struggling to keep the glazing I want. The paper I listed above showed a comparison between IES VE and EnergyPlus and the conclusions included "Significant differences were recorded between predictions, with the EnergyPlus models recording a high overheating risk in seven out of the nine cases, while IES VE predicted a low overheating risk for all models." That suggests to me some TM59 game playing by choosing the package that comes up with the most helpful results? I can't help feeling that Part O is very badly thought out. I'm reading a bunch of stuff on PHPP & TM59 right now.

Ah, thanks I see you have an image in this thread: https://forum.buildhub.org.uk/topic/31617-ideas-wanted-to-pass-part-o-simplified-modelling-or-to-use-dynamic-modelling/#comment-467880 FYI another couple of things I couldn't get a clear steer from the 'regs' (in the Part O Guidance) are: + there doesn't seem to be any sense of angle to the sun in the Simple Method - so roof lights are a bit problematical. Which compass direction are they facing - well often mostly 'up' of course. + in a similar vein, if you have roof lights over a 1+ storey void, then do they 'belong' to the ground floor or to the one above? + re security - if you live in the countryside, is it considered 'secure' (only for the purposes of these calcs) to sleep with ground floor windows open? Doors? (As far as we're concerned we normally sleep in summer most of the year with ground floor bedroom windows open.) And general observations: + Part O is all about the problems of solar gain, nowhere does it mention or consider the benefits (economic / climate / amenity) of solar gain. + The actual TM59 software mentioned in the Guidance examples is: IES VE 2021 3.1.0 (this is 'send for quote') TAS software v9.5.2 (£200 p.m.) - it's curious that CIBSE has specified in TM59 some simulation and CFD calcs without specifying (a) exactly what those calcs are, (b) a list of software which is deemed to observe the calcs, (c) a verification method for that software. I see also that DesignBulder software claims to be TM59 compliant and uses the free US-based EnergyPlus for simulation and HVAC. There's some TM59 notes for using it here: https://designbuilder.co.uk/helpv7.0/Content/CIBSETM59.htm

@Susie - thanks is it possible to add an image of the elevations so we can get an idea of what that % of glazing looks like in practice? TIA, Alan

Well I've been researching this some more and thought I would post an update: + The headline is that this looks a significant can of worms for a lot of self-builders unless you have very mass market design sensibilities. Barratt home anyone? + This video by Pilkington says (about 1/2 way through) (roughly) 'yeah, if you want Grand Designs, then the Simple Method won't work for you'. https://www.youtube.com/watch?v=NrY7odmPm68 + I did a rough-and-ready 'Simple' analysis of our current design. If my calcs are correct, then we're way over the limits atm. + There's a lot of the 'Simple' procedure which doesn't make a lot of sense to me e.g. why would you want to limit North facing glazing? + @Susie - as you have pointed out, there's no allowance in the 'Simple' method for any mitigation like the various forms of shading etc. So the proven Mediterranean methods: outside shutters / awnings / vegetation etc etc etc are totally ignored as are modern methods e.g. Pilkington's low-transmittance SunCool glass. + That suggests TM59 modelling may often be necessary, which might be properly expensive if you get someone else to do it. + There's a comparison of a couple of modelling packages here: https://journals.sagepub.com/doi/pdf/10.1177/0143624418792340 + And I note that one of the two pieces of software mentioned there: EnergyPlus, is free https://energyplus.net/ All-in-all quite a complex headache IMO. Designed to protect city flat dwellers who largely have to live with what they've got (and cope with the window opening implications re noise / pollution / security / safety), I question the relevance for self builders who usually have control of their own building and can therefore retrofit (e.g. shutters / awnings etc) later if they find they have a problem. Also, bulk house builders will only have to model a 'sample of homes' (and Part O doesn't give hard criteria for the sample) and therefore they can spread the costs over an entire development, whereas the self-builder will usually need to do a one-off i.e. 100% analysis. Hmm, another little industry and new build tax has been created.

Well I think 'O' is badly thought out. 'No benefit from trees or curtains' is dumb'. Our present place was v. hot at times before we planted the garden up and put in some thick curtains. (We didn't design it and its a barn conversion, so lots of the design decisions were made in the 1850s.) It's fine now and the plants we've used love the sunshine. I think my strategy will be to apply for planning with ample glazing and then reduce glazing / add solar mitigation with non-material amendments as necessary. There's no point in doing all the calcs if planning hates the design for other reasons. And planning won't be that bothered if we want to reduce the glazing later.

Well I just read through part O - my first reaction was hilarity . The expectation is that you do this after you've adjusted your windows following your heat loss calcs and before your planning application? "Despite its name, the Simplified Method is not entirely simple". Yeah, well.

I believe so if you change the GIA. Maybe if you have a 'bit that you could chop off' or other simple amendment rather than a complete re-design you might get away with a minor amendment. In theory your planners should be able to tell you based on an simple description of your proposed changes. Depends on how helpful yours is. A number of LPAs have a description on their web sites of what they think is minor/non-material.

>>> What is the benefit of a mortgage advisor specialist vs self serve. I think it boils down to how standard your situation is. If it's run-of-the-mill then self serve is fine. If it's a bit special, then broker. There's nothing to stop you doing both in parallel and taking the best deal.

If it's any consolation I have a bunch of pipe and plasson fittings which looks as messy. It would look better if plasson just made the caps in black or 'pipe blue'.

>>> Not worth a knitted flue cosy. I think that something striped and crocheted would be lovely.

>>> The law of conservation of energy A very clear explanation, thanks. And I thought that 'conservation of energy' was something to do with lying on the sofa and being too lazy to get the remote. I should have paid more attention in school.

>>> I thought it was around 15p/kWh? Yeah, I think you're right. BTW the Octopus Agile pricing suggests a 120% markup.

Oh dear, I seem to have started something...

>>> average wholesale price they pay is around 5p/kWh OK, well I guess it's about time I started my electricity markets education... https://www.ofgem.gov.uk/energy-data-and-research/data-portal/wholesale-market-indicators These do seem to suggest 3-5p per kWh. So, why are we being charged anywhere between 15-43p? The fuel markets seem to have only a 50% markup? https://www.racfoundation.org/data/wholesale-fuel-prices-v-pump-prices-data

If you can split your panels into groups that are shaded at the same time and this arrangement suits your inverter (number of input connections, min/max DC voltage in etc) then you should be home and dry.

>>> Just been onto Eon Next and they now say they need a photo on the electic connection in place before they will book a installation, which will be in 6-8 week wait! That's for meter installation on a new line, or just a meter swap? For a straight meter swap, I've contacted Eon.Next by phone and by email (different groups I think) and both told me 'someone would call to make an appointment'. That was a few weeks ago now. I got another couple of invites from Eon.Next for a smart meter install yesterday. I fall for it every time. Answer their questions ... then it thinks for a few seconds and says 'no meter installs in your area'. Well why did you xxxx send me an invitation then...

>>> I'm curious why you consider grid export a "luxury"? Well tongue-in-cheek i.e. giving someone else power at a small fraction of the price they would sell me the same thing. I don't have much of an understanding of the electricity markets, but the general feeling here, I think, is that the DNOs are taking the ... mickey.

Never one to miss an opportunity for analysis:

>>> So with a bit of forward planning, if you heat water and charge batteries around the high production times, your house will be less hot. Whoo that's v. clever.

You guys are fantastic >>> Are you talking of a totally off grid system? Probably with batteries? I was actually thinking of something like that i.e. without the 'luxury' of dumping excess power back to the grid. Seems then that the panels will just heat up more when the 'full load' is not extracted? Thanks also for the answer to the PVGIS question - I was quite liking the 20 degrees roof slope anyway as it gives max internal space with a nominal 1.5 storey / 7m ridge height - so that adds another plus.

(1) PVGIS seems to give me 67% power output for North (vs. South) for Suffolk. Is that really right? Azimuth kWh p.a. / kWp % vs. S Westerly 125 780 74% Easterly -55 986 93% Dead North 703 67% Dead South 1,057 100% This is for 20% roof slope. (2) What happens if you don't draw the max available power from your panels at any time? And you don't actively divert it to heat hot water or send it back to the grid? Does it end up as heat at the inverter or maybe in the panels themselves? Or something else?

Well there's a couple of other suppliers mentioned in the thread so far, and I, for one, would be interested to know who these great suppliers are. I need 3 replacement sashes atm.

For anyone based in East-Suffolk and/or thinking they might build there someday, the LPA are soliciting feedback on their 'Supplementary Planning Document?' re custom and self-build housing policies. So, this is your chance to have your input to 'the rules'. See: https://eastsuffolk.inconsult.uk/CSBSPDINT/ The consultation runs from 1st Feb to 15th Mar.