Alan Ambrose

I think that all stove / flue / chimney work, inc refurb, needs either a Hetas-qualified person (who can self-certify) or alternatively BC sign-off.

>>> We'll be managing the build ourselves, as we've decided against having a main contractor. Maybe we'll need a project manager at some point. I’m all for DIY - as long as your skills are up to the job. But it’s good to be aware of the areas where you don’t have skills / knowledge / qualifications / contacts and have a plan for sorting those. Some questions: + do you have a ready supply of good quality trades, if not where are you getting those from? + do you have the time to draw detail designs / do purchasing / calculate quantities / run planning, building control, warranty, cdm etc paperwork / inspect work on site / review contracts and quotes? + do you have great analysis & decision making skills / risk management judgement / know when to take pragmatic choices? + are you resourceful in a jam? Properly practical? Know how and when to push trades out of their comfort zone? Good at managing unsophisticated teams? + ever done anything like this before? Built an extension, done a refurb etc.

>>> I was thinking of appending an external socket onto kitchen ring and an external socket on to ground floor ring. Also a dedicated circuit for external lighting that combines both front and back. We have this in our current place - all as switched fused spurs. Proper outside sockets are fairly reliable, so shouldn’t be a problem. The outside BG sockets have their own rcds.

>>> Been 'a thing' since the 18th Century? I wonder what the logic is as a typical microwave is ~1kW and a Quooker is ~1.8.

I’m using Vantage based in Earl Soham, prob not so far from you. Seem good, but I’m not looking to them for advice (as above) and have solicited their views on only a couple of details.

@billt >>> My system is off grid and AC coupled using SMA inverters. Is that totally off grid? You have generator back-up or something similar?

FSCables has been recommended on 't 'ub for Cat6. Also, I've used them for multicore e.g. for LED strips.

I wouldn’t underestimate the variable quality of these pipes (like everything else). Would you want to be making them for a retail price of £2.50? How would you bring the cost down? Reduce the thickness and quality of the bit you can’t see i.e. the rubber pipe? Make the braid out of shiny metal rather than stainless? Who fitted the ones you have and where did they come from? I would buy the best quality branded ones I could find, probably replace all you have, and see how well those work.

Some Stanford Prof, I forget his name, predicts that we'll eventually get massive over-capacity in renewables and thus cheaper power prices eventually. Don't heckle me, it's not my idea. However, if a bit of that is true then the peakers will be used less and less over time and therefore gas will eventually become less of an influence on electricity prices.

In this recent video, there's a couple of comments that I'm not sure I quite get. Here's a link to the video: Why Are The DNOs Limiting Your EXPORT And Even Your INVERTER SIZE? https://youtu.be/Bvpl9pvg8zk?si=4rLhJ-me57Pcwabu Here are the two comments (I've highlighted the relevant bits that were raising questions for me in bold): >>> One detail - only grid tie need approval. If your system isn't capable of pushing power into the grid (that's not capable as opposed to "set to 0") then you sidestep it at the cost of no export revenue. Setting up a big non grid tie inverter and putting the house on that with the grid as an input (generator basically) lets you side step all the mess in the difficult cases. It's not usually the best option but if you are getting 3.6kW and especially if you are also refused G100 with a bigger inverter it's definitely worth doing the maths on houses where you want bigger batteries and inverters, and remember it also lets you avoid the MCS costs too. I am guessing plug in solar is going to make it even more of a circus especially if they got 250,000 G98s submitted the month it goes legal 😎 Our setup actually has some grid tie with grid tie batteries and solar, and some non grid tie with other batteries/solar that runs the heatpumps and some other bits. It was the only way to make this big old building work within the allowed G99. <<< >>> The inverter size limitation is to do with failure cases with export limitation. If they calculate that the export limit fails, and the resultant voltage would exceed legal upper limits at your house, and your inverter voltage shutdown protections also fails, then they impose a choice: 1. Stipulate Inverter size limits, 2. Provide a quote to the solar installer for reinforce the DNO’s network so that it can accept the higher inverter size (often many thousands of pounds). At my house, I have an 8kw inverter with a 5kw export limit. When exporting 5kw, the voltage is about 247V. So there is some headroom between the export limit and the upper legal voltage. There are two a get out clauses though: 1. Install a 3.6kW inverter, but with 7kW Maximum Power Point Trackers. That enables you to hookup 7kw of solar, and at maximum power: 3.4kw can be fed to a dc coupled battery, even though the AC output is limited to 3.6kW. Sunsynk offers such an inverter. 2. Don’t connect your inverter to the grid. DNO’s only have jurisdiction over connections to their network. They have no jurisdiction over off grid systems. You could have an 8kw+ inverter supplying your house off grid. Then you can choose whether your house is connected to the grid, or your inverter, using a changeover switch. There’s no opportunity for export, or charge up with cheap overnight electricity though. <<< The reason I'm asking is that I'm planning on having a lot of panels and inverter power and self consuming as much as possible. I'm planning on over capacity so that I can make the shoulder seasons (i.e. spring & autumn) mostly self-consumption too. I don't really care about the export - I'm guessing the rates will continue to fall until it's a waste of time.

@Roger440 re: They could have completely de-linked it. You have a scheme for that? My understanding is that it's the gas-driven 'peakers' that provide power when everyone else is at max output (or offline) - hence it revolves around the price of gas.

One of the effects of the current mechanism BTW is that conventional generators including renewables get windfall profits every time the gas price spikes. Even with 'the levy'. I dare say they like that. As long as the gas peakers are needed then the marginal price will largely be set by gas. Peaking power plant - Wikipedia >>> New plans include long‑term fixed‑price contracts for renewables, protecting families when gas prices spike The financial markets are very quick to create new futures / forwards / options / swaps / CFDs etc if they think there's any demand - they don't need any government help to do that. All-in-all the current industry players are not unhappy with the current situation.

I've been looking at this issue and talking to my BC guy. His opinion is: Fire stopping cavity barriers are not enforceable under building regulations for individual domestic dwellings. Only enforceable in buildings with separate compartment ie flats or semi’s. Although I do think the fire stopping strip is a good idea it is your choice in this circumstance. I suggested this stainless metal strip (we already have 25mm ply around the window apertures), which would work well for us: https://www.roofingsuperstore.co.uk/product/terne-coated-stainless-steel-fixing-strip-50mm-x-20m-roll.html And his response was: I think metal is a good option although not seen it used, timber or fire socks (fibreglass) are nearly always used.

I’ve a bunch of these, most of which have been there for 30 years. No problems except for one within one of those shower-hose-like kitchen taps. I wonder whether some are much better quality than others? Real stainless shouldn’t rust much with standard water. Agree that relying on the rubber hose isn’t the smartest.

Thanks, that's interesting. I also just found that 21 degrees offer the open/close sensors too, but no more detail than that right now.