Integrated garage conversion DPM/DPC beginners questions

[RobMill]

Hi all,

As the title suggests I am considering converting our integrated garage into an office room. I'm considering doing some (ideally most) of the work myself but having not completed something like this before am just setting out to learn some things before committing one way or the other.

At the moment the biggest bit of unknown is how to deal with the floor and damp proofing etc.

The external walls to the garage all look good and have the DPC where it should be - no problems with damp inside the garage as far as I can tell.

So what is the normal plan of action?
1- Apply a DPM (Liquid or sheet?)
2- Level the floor with a screed (I've read some do / some don't - I'm not sure I have the depth as the drop between the house and the garage is about 40mm - I read screed should be 70mm+ so it doesn't break?)
3 - Put down a layer of 50mm foil-backed insulation (A builder had around to quote on the job mentioned this? I guess more is better but I am trying to minimise the step up from the house to the garage... thoughts?)
4 - Chipboard directly on top of the insulation

Taking some inspiration from this chap:

Any advice/links to further reading much appreciated!

Cheers,
Rob

 

[Bonni]

A garage conversion involves building regs, so there's a starting point. Building regs might want 100mm Kingspan in the floor.

 

[RobMill]

Cool so the best bet is to just get them involved / over for a look and see what they recommend. Makes sense
Cheers, Rob

 

[Leofric]

Cool so the best bet is to just get them involved / over for a look and see what they recommend. Makes sense

No, it isn't up to Building Control to tell you how to build it, they aren't a design service. The procedure is you make a Full Plans Submission or do the work under a Building Notice. There are lots of posts on here about 'which way to go'.