Slight issue with door threshold! 30mm out

[2020c]

Been building an extension these last few months in different stages. Foundations where out 25mm over an 8.5m length which isn't much. The block layer was supposed to take this out in his beds of mortar which he didn't! The window supplier measured of the dpc level when he measured for the doors a few months back. Now it's plastered out, it's time to install the insulation and screed on the sub floors, I now notice the finished floor level is out 30mm from one end to the building to the other and is above the door threshold.

Block layer to blame although I should have checked it before doors where measured so I share some of the blame too. Anyhow, what can I do now with this. What I am thinking, I could maybe lose 15mm in the hallway and 15mm in the room but would one feel a 15mm fall in a floor?

My other option is to have a 30mm step into the hallway from the room but was this not be very noticable.

 

[Swwils]

How much insulation are you putting down?

 

[2020c]

How much insulation are you putting down?

150mm . It's the finished floor level coming from existing house to the furthest away location of the new extension which has a double door is the issue. I can't see how insulation depth would effect this.

 

[Swwils]

it's time to install the insulation and screed on the sub floors

So you can make up the height by reducing the insulation but maintaing performance, which you could do by selecting a better performing insulation that would require less thickness.

 

[2020c]

So you can make up the height by reducing the insulation but maintaing performance, which you could do by selecting a better performing insulation that would require less thickness.

It's not the height I'm looking to make up. The door threshold is 30mm below what it should be. The double door was made to big by 30mm and if I keep the floor level as should be , then it's above the door threshold. In that room I could lose 15mm of a slope in 4m length and 15mm in the other 4m length in the hall with a slope but I'm wondering how would that feel walking on it. Would one notice a 15mm fall in each room. A door sadle in the interior door with a drop of maybe 15mm or a 30mm drop at the door sadle.

 

[johnny2007]

Although 15mm over 4 metres won't be noticeable, don't do it.
What I would do is level the lot and get the french doors shortened.
It's an hour work for any upvc workshop and if you can take the glass out and the frames there yourself, you could save some money.
Overall it shouldn't cost you more than a couple of hundreds.

 

[2020c]

Although 15mm over 4 metres won't be noticeable, don't do it.
What I would do is level the lot and get the french doors shortened.
It's an hour work for any upvc workshop and if you can take the glass out and the frames there yourself, you could save some money.
Overall it shouldn't cost you more than a couple of hundreds.

Not where I am. 10 week delay in getting these doors and windows!

I'll ring them tomorrow see what they can do but I can't see them fixing this by next week.

 

[mrrusty]

The window supplier measured of the dpc level when he measured for the doors a few months back

Assuming no floor when he measured up, how did he know DPC level would be appropriate for FFL? Were there plans? did he assume? Did you tell him?

 

[2020c]

Assuming no floor when he measured up, how did he know DPC level would be appropriate for FFL? Were there plans? did he assume? Did you tell him?

He was told about it.

But after remeasuring with lase level, the floor is out 18mm, not 30! Be alot easier to take this out. I could lose a few mm where the opening is for the new enterance is into extension, slope it 7mm over 4m to the doorway into new room and lose another 7mm in that room to the door or keep that room level and have a door sadle at the door with adjusting the height or adding 6mm under one side.

 

[John D v2.0]

So if i understand correctly, the ultimate problem is the door is an inch too high, if so another option is to lift the lintel slightly. That should take less than 10 weeks and be cheaper unless there's something preventing that.

 

[cdbe]

You can trim the ribs off the top of a uPVC door - about 8mm.

 

[Mr Chibs]

Just a thought, could you change the bottom door frame to a low threshold version? Is it single or double?

I have one on my back door, it’s only about 10mm thick.

if not, any chance you can butcher the frame slightly?