We’re thinking of converting an outbuilding we have into a new office for me, so that we can integrate my existing office into the house as it’s attached.

I’m going though the stuff we’d need to do to make it work (internal insulation, ceiling, new windows, etc.) and the one thing I’m not sure how to deal with is the floor.
I currently has a concrete floor that slopes from the far end of the room to the door that made cleaning easier (it’s actually a stable). I’d want a level floor which would basically be a bit of insulation under engineered wood.

What might be the best way to level off the floor without digging it out and relaying?

Could you batten it to level, then board over the top, with insulation under battens? Means they’d be a step up to get in, of course…

Yep, a step up was always going to be required. I was wondering if battens are the only way….

How far out is it? And where would it need to be in relation to adjoining rooms? Is there an existing DPM?

Clean,etch, prime and pour a new slab on top of the old one. Assuming existing slab is in good shape.
Unlikely that there is a layer of insulation under the existing.. So dig out, ridgid foam and concrete on top is an option.
As markie, Building a raised sub floor using timber and insulate the joist gaps would be cheapest and easiest I reckon..
I did this when enclosing an entry way. Vapor barrier then 2×10 on end ripped from 1″ to 8″ to level the slope along the run. 3/4 ply, ditra then tile and its sold as a rock.

If you don’t need underfloor insulation and already have a dpm, build up a wall on the lower side and then use self levelling gloop?

I doubt there’s a DPM but it’s dry and actually has some sort of rubber finish on (some horsey thing I guess). No connection to another room that matters.
Insulation would be nice,but not imperative.

I’ll have to get the laser level out and see what the fall is.

This sound pretty like what I did with my gallery project. I made a ‘floating’ wooden floor as I had lots of headroom.

http://www.petermclarenfineart.com/Blog/GlassmountGalleryProject

I thought you may have done that MM but hadn’t looked back at the thread.
My floor drops 13cm over 5m so I think the same floating floor will work fine. I too have no height restrictions so no probs there.
I shall have at look at your thread again.

My floor drops 13cm over 5m

😯

I thought we were taking maybe an inch or so. I think a new suspended or floating joisted sub-floor (which you can easily insulate) is yer only man there. Engineered floor (with liquid batons and tongue-tite screws) will be a doddle over those.

I’d look at using a screed on top of the concrete to level it out.

If it’s concrete it could be very cold. Wooden battens give you the chance to install insulation at a decent depth beneath. Floating a self level ending screed would be level but just as cold.

We have a solid concrete floor in our utility room – never again! It’s freezing.

Screed would be cold if not insulated, but screed and insulation aren’t mutually exclusive. (I’m just lazy and couldn’t be arsed with all the wood work).

I’d look at using a screed on top of the concrete to level it out.

5″ screed? No thanks.
Floating joisted sub-floor it shall have to be – probably fairly cheap anyway.