The MN surviving building an extension thread of hints and tips

[WhereDoesThisToiletGo]

The ongoing Extension threads are full of useful stuff but I thought it could be helpful to have a separate resource thread with more hints and less chat.
Please feel free add things to that helped maintain your sanity!

Links to products are useful but please also include a description as links can go out of date or be removed by retailers.

Where possible, I have tried to credit MNer who had the tip...

Make sure you check or update your home insurance @MyNameIsJane
You may need to add a small premium. Some insurers will refuse to cover you but should refer you to an alternative insurer.

Zip up dust door @WorrisomeHeart
Keep the extension and "untouched" bit of the house separate

If you are having a skip on your drive, ask the builders to put down boards before it is delivered. This will protect your drive from damage as they tend to slide around during the changeovers
Various available on amazon

Do tell your builder if anything doesn't look right straight away. We did and it saved it becoming a huge problem later. ( Door was 20cm out)

Write out a spec room by room. No. of plugs, lights, any carpentry, go to the nth degree. Ask for quotes to include everything. Any items such as bathrooms, doors, ironmongery, garage doors, ask for their £x allowed for. They can then sign for this job, with these plans, to cover these items. It also makes comparisons much easier.

Ask to speak to a current job. Speak to 2 previous ones too. Make sure their name is on a board (or similar) outside. Do not believe phots unless their van or sign is in the shot!

Ask your builder to write to your neighbours and knock the doors of those next door. If the neighbour is a shit (like ours!), he may as well tackle them early on.

Consider knocking it down. We should have really, but got attached to the old building. It would have been quicker and cheaper!

Discuss how much outside storage and working space the builders actually need. If you give them full access to your entire garden, they will fill it with stuff and trash it. Cordon off as much as possible. London builders are used to dealing with bad access and minimal storage space.
We were fortunate to have a large block paved area at the front which they used so the back and side garden escaped fairly unscathed

When you are planning your budget don't forget to include delivery charges in to the cost of the item, £150 for flooring, £30 extra on tiles etc. So far delivery charges alone are up to £430 it's very easy to miss.

It's quite easy to get carried away during kitchen design with fancy internal fitments which REALLY jack up the cost.
I wanted to keep plates in deep drawers and thought I would need fancy drawer dividers to stop them sliding about but decided to wait until kitchen was in and add them later if required.
Instead on spending £90+ on a gorgeous wood peg board plate holder for a single drawer, I spent £16 on good quality non slip shelf liner roll which did 4 drawers and NOTHING budges!
I also bought shallow non slip drawer tidys (set of 3 for less than £5 from somewhere like B&M or Home Bargains) which keep the utensil drawers and Drawer of Random Crap in order.