Replacing all ground floor joists

[ToastyToes]

I'm in the process of major renovation works which had led me to ripping out every ground floor joist.

The original timbers are 4x2 but I will replace them with 5x2 or larger so it is more sturdy.

I don't want to lose the ceiling height by having bigger joists so the plan is to remove a course of bricks on the dwarf/sleeper wall and mortar on another wall plate for the joists to sit in.

Does anyone know if this acceptable? Can I take out a course of bricks around the bay window? I will be below the original DPC but I will ensure I lay DPC under the wall plate.

Thanks.

 

[freddiemercurystwin]

Or stick with 4x2s but do them at closer centres.

 

[cdbe]

Or notch the ends an inch where they bear - virtually no effect on strength - clever people on here could explain why. Or 4x3s, and get some insulation between them.

 

[blup]

Whichever course of action you follow remember to insulate under the new joists where they sit on the sleeper walls.

Blup

 

[ToastyToes]

Or stick with 4x2s but do them at closer centres.

Could do but I would still feel more confident with thicker timbers under my feet.

Or notch the ends an inch where they bear - virtually no effect on strength - clever people on here could explain why. Or 4x3s, and get some insulation between them.

Hate the idea of notches. It creates a weak point in my eyes. I wouldn’t be able to sleep.

Whichever course of action you follow remember to insulate under the new joists where they sit on the sleeper walls.

Blup

Definitely. Thanks

 

[foxhole]

An inch difference in ceiling height is undetectable by anyone unless they are carrying a tape measure .

 

[ToastyToes]

An inch difference in ceiling height is undetectable by anyone unless they are carrying a tape measure .

You don't know my Mrs

 

[foxhole]

So are you covering floor with cheap thin carpet in case it make the ceiling look lower.

 

[ToastyToes]

So are you covering floor with cheap thin carpet in case it make the ceiling look lower.

Minimise where we can so we can have better flooring on top

 

[StephenStephen]

I reduced the dwarf wall height underfloor recently - I was a little unrealistic as to the amount of work to level the joists (but then I was using a mix of new and old joists, and it's a very old house with layers of strange building history).
It might be worth considering what else you might do whilst you've the floor up - clear out the space, check airbricks, insulate and draft-proof the floor, put in an underfloor safe, lower the floor further, wiring etc

 

[endecotp]

It might be worth considering what else you might do whilst you've the floor up

Insulate all the pipes!

 

[ToastyToes]

I reduced the dwarf wall height underfloor recently - I was a little unrealistic as to the amount of work to level the joists (but then I was using a mix of new and old joists, and it's a very old house with layers of strange building history).
It might be worth considering what else you might do whilst you've the floor up - clear out the space, check airbricks, insulate and draft-proof the floor, put in an underfloor safe, lower the floor further, wiring etc

I have already cleared over 8 yards of rubble left by previous owners.. took a whole weekend to dig out!

I will use 100mm Celotex insulation.

I have also installed new double air vent bricks every 2m or so. Lots of ventilation now.

 

[foxhole]

Minimise where we can so we can have better flooring on top

Just plain dumb idea.

 

[Anstiss Ltd]

Just plain dumb idea.

Tbf raising the floor heigh will have implications on doors etc

He asked about the feasibility and best way of dropping the dwarf wall.

Not weather it was a good idea or not.

For me a new wall plate on a bed of morter also protected with a dpc is fine.

The dwarf wall only supports the floor so lowering it makes no difference.

 

[foxhole]

Tbf raising the floor heigh will have implications on doors etc

He asked about the feasibility and best way of dropping the dwarf wall.

Not weather it was a good idea or not.

For me a new wall plate on a bed of morter also protected with a dpc is fine.

The dwarf wall only supports the floor so lowering it makes no difference.

Seems pointless to give advice on a pointless task.