Given the details below how much do you think we should budget for a fitted gas boiler? Any product suggestions or other matters we need to consider?

Passivhaus/EnerPHit refurb, MVHR, 3 bedroom, 1 bathroom (1st floor), 1 en suite (2nd floor). We want to locate the boiler at ground level in a WC/laundry next to kitchen (and below bathrooms/en suite). Venting will either be through the dining room to rear wall (about 5 m) but onto a patio, or across into and up through new roof of rear extension.

£0

Ok tony no need as PH , but what about HW if no Solar , electric immersion /ashp all a bit pricey
ah ha crossed posted with you there

Wow, that low, we were thinking we'd be looking at £2500, super efficient jobby.

Gas boiler fitting is simple enough and emminently DIYable. Make hole in wall, stick flue through, screw boiler to wall, connect up water, gas and condensate drain. Check for leaks and final pressure with manometer. There are a load of rules about flue location (distance from eaves, windows, roof line etc)- check your plans fit those. Flue length is determined by the boiler. If you want a really long run only some models will do. (there were some models I saw at ecobuild this year with non-concentric flueing so you could do 50m if you wanted).

I paid £800-odd for a Veissman system boiler plus fittings. Took a weekend to fit.

Nonsense; they make it illegal to fit other people's for money. I'd expect you to know that Tony. You just need to be 'competent' which is not defined in terms of club membership, just actual competence.

Posted By: wookeyNonsense; they make it illegal to fit other people's for money. I'd expect you to know that Tony. You just need to be 'competent' which is not defined in terms of club membership, just actual competence.

That's correct , but I believe it would fall under building regs. as you couldn't self certify, so you have to go via them if DIY (officially) if there onsite due to other works then it's simpler

<blockquote><cite>Posted By: jamesingram</cite><blockquote><cite>Posted By: wookey</cite>Nonsense; they make it illegal to fit other people's for money. I'd expect you to know that Tony. You just need to be 'competent' which is not defined in terms of club membership, just actual competence.</blockquote>
That's correct , but I believe it would fall under building regs. as you couldn't self certify, so you have to go via them if DIY (officially) if there onsite due to other works then it's simpler</blockquote>

It does indeed fall fairly and squarely under BC if you DIY a gas installaton, as compliance with Part J is normally delegated to the Gas Safe company/individual doing the installation. The level of competence required for someone installing a gas appliance is fairly well-defined in Part J (see below) and wouldn't be met by many DIY'ers unless they have undertaken some training and certification.

I believe that if you ignore the regulations and do fit a gas appliance yourself, without the appropriate safety check and sign off by a competent person, then your house insurers may have a problem in the event of a gas-fault related claim. You would almost certainly be liable for any civil damages costs arising from an incident and if someone was injured or killed you may well be found criminally negligent for knowingly breaching the Gas Safety (Installation and Use) Regulations.

I'm not great supporter of regulations and the closed shop organisations that spring up to provide "competent person" cover, but in the case of gas I would tend to err on the side of caution and get any installation checked and signed off. Having said that, if it's run safely for some time and you're confident that it's correctly installed and set-up then the risk of such a problem arising would be fairly small.

For reference, here is the text of Part J that applies to competence:

<i>"The Gas Safety (Installation and Use) Regulations require that

(a) gas fittings, appliances and gas storage vessels must be installed only by a person with the required competence and

(b) any person having control to any extent of gas work must ensure that the person carrying out that work has the required competence and

(c) any gas installation businesses, whether an employer or self-employed, must be a member of a class of persons approved by the HSE; for the time being this means they must be registered with Gas Safe Register.

3.3 Guidance on the individual competency required for gas work is available from the Sector Skills Council Energy and Utility (EU) Skills [http://www.euskills.co.uk/gas]. Persons deemed competent to carry out gas work are those who hold a current certificate of competence in the type of activity to be conducted. Assessment of competence may be through the S/NVQ qualification under a nationally accredited certification scheme or under the Approved Code of Practice arrangements.

3.4 The Gas Safety (Installation and Use) Regulations control all aspects of the ways combustion systems fired by gas (including natural gas and LPG) are installed, maintained and used, mainly in domestic and commercial premises, and the classes of persons who may undertake gas work. The Regulations may be amended from time to time and whichever Regulations are currently in force at the time an installation is carried out must be complied with.</i>