Graham,

Thank you for the heads-up.

So now I am left wondering about 2 things.

(1) Upgrading my fire alarms - TBH, it should have been done years ago, so perhaps it is not as relevant as it seems.

(2) Whether the battery would be better in the loft with the PV tackle; or in the (detached) garage. Putting it in the loft makes more sense to me especially because in mine there is a largely redundant distribution circuit of 10 or 16 mm² cable (I have not looked closely yet).

A neighbour is delighted with his PV array and 9 kWh battery - his are in the integral garage.

So which is better: a battery in the loft, which might cause severe damage to the roof; or in an integral garage, which could burn the whole house down?

I think that my vote is for the loft.

Chris Pearson said:

(1) Upgrading my fire alarms - TBH, it should have been done years ago, so perhaps it is not as relevant as it seems.

The IET CoP has referred to BS 5839-6 for this particular topic since the 1st Edition in 2015. What's confusing is that BS 5839 series is a "Code of Practice", and therefore has "recommendations" ("should", "recommend") rather than requirements ("shall" like in BS 7671). However, if you are applying a Code of Practice, to comply you need to fulfil all of the recommendations ("should"/"recommend") clauses, whereas to state conformity to a standard, you have to comply with all of the relevant requirements ("shall") but not recommendations ("should"/"recommend").

Chris Pearson said:

(2) Whether the battery would be better in the loft with the PV tackle; or in the (detached) garage. Putting it in the loft makes more sense to me especially because in mine there is a largely redundant distribution circuit of 10 or 16 mm² cable (I have not looked closely yet).

I would be inclined to ask your insurer the question ... but you might not like the answer depending on the particular insurer. Some will say "detached garage or outbuilding" (and some of those might say "at least x m from the main house"). Similarly with EV charging ...

Chris Pearson said:

I think that my vote is for the loft.

As above, some insurance companies may not agree.

gkenyon said:

As above, some insurance companies may not agree.

I have never yet seen an insurance policy that specifies where you are allowed to put batteries.

Simon Barker said:

I have never yet seen an insurance policy that specifies where you are allowed to put batteries.

Perhaps let's not tempt fate, especially where certain lithium battery chemistries go. - it's becoming a popular thing to talk about ... along with EV and Solar PV. There is definitely insurance-sector guidance on these subjects, and some insurance companies have their own.

Simon Barker said:

I have never yet seen an insurance policy that specifies where you are allowed to put batteries.

Perhaps let's not tempt fate, especially where certain lithium battery chemistries go. - it's becoming a popular thing to talk about ... along with EV and Solar PV. There is definitely insurance-sector guidance on these subjects, and some insurance companies have their own.