Costs for management and insurances for health and safety for building extension

vinodnalla

We are doing a single storey extension to our kitchen and home refurbishments. One of the builders has mentioned in his quote that - "We have not added any costs for management of the scheme, our insurances for health and safety."
We asked the builder for clarification for which he said they are going to charge us 10% which is a standard figure for the management of running any scheme, as well for health and safety, insurances, (public /employers liability insurance) . Is this something common and do we need to take it? We have a building and content insurance and plan to inform our insurer about the building works.
Should the management of the building works and employers insurance be provided by default by the builder?

Doozergirl

I wouldn't really be having that conversation with people usually. If I'd written the quote then standard overheads would just be in there as a margin, but the builder can charge things out as they see fit. There isn't a rule.

Have you given them a tender-type document with space for prices for individual items? It's hard to spread the preliminaries for a job across the whole cost if the client wants to treat it like a shopping list to pick and choose from, or if it's a complicated job that involves lots of specialist paperwork. In which case, you'd look to separate it.

Mistral001

No this is not usual for small extensions. Why the builder is adding all these items as if they are extras instead of just necessary costs that every builder has to bear on every project, is a bit of a mystery. One thought is the rise of the project manager where there is not a lump sum price.