floor flex

[quick draw macgraw]

Hi All,

Any suggestions how to best support this floorboard where it meets the concrete as there is no joist at the point of meet and as i,m overlaying with 6mm backer still be too much flex.
Was thinking of wedging some 3x2 up to underside and screwing down.

cheers Steve.

 

[howard]

what about expansion foam ?

 

[quick draw macgraw]

never used it mate but dont think i'd be confident using it.

 

[Gazzer]

how deep is the void? woould you not be better using sand and cement?
Cut back the over hanging boards and fill the gap. i would put an expansion joint in anyway where the 2 meet.

 

[howard]

Ive seen it used in the same situation on site there was no movement after and it lasts for years

 

[quick draw macgraw]

Didn't actually measure the void as that option didn't occur to me will prob have another look to see if its viable. Aware of the expansion joint thanks.

Steve.

 

[quick draw macgraw]

If the sand cement option was took where would the expansion joint go? where boards meet sand,cement. But what about where sand cement meets concrete?

 

[Gazzer]

Where the wood and screed meets. Never had a problem where screed meets screed before. What method are you using to fix. Overboarding ,Ditra?

 

[grahamster]

i would go with sand & cement,with a few bricks to fill in most of the gap.then top of with more sand & cement.

 

[quick draw macgraw]

Because of the height difference was going to use 6mm backer boards on the wood.

 

[grumpygrouter]

Is it practical to lift the boards and secure timber to the concrete to fix the boards to?

Grumpy

 

[DHTiling]

Lift the boards up....insert damp proof membrane and fill void with rapid setting concrete mix...once dry relay the boards and fix the boards to the new concrete to support the edges......then just insert the movement joint at the end of the boards..........

 

[quick draw macgraw]

Any particular damp proof membrane and is there a cheap quick setting cement around as it will all come from my quote although i'd rather it be right 1st time than spend more money putting job right after problems.

Thanks steve.

 

[quick draw macgraw]

Hi grumpy do you mean pull the boards over and fix to concrete? If so i'll have big height difference which would give me personally a bigger headache than filling in with cement.

Cheers Steve.

 

[grumpygrouter]

Hi grumpy do you mean pull the boards over and fix to concrete? If so i'll have big height difference which would give me personally a bigger headache than filling in with cement.

Cheers Steve.

No mate, I meant that if you lifted the boards you could then put a supporting piece of timber along the internal side of the concrete and then extend the boards across, level with the concrete surface and secure the ends of the board to the supporting timber. Sort of like putting an extra joist in but only screwed/plugged to the concrete, if you see what I mean.

Grumpy

 

[TheWrightTiler]

only option id use would be to lift the boards
stick a baton against the concrete edge and screw it to the concrete using a glue to hold in place also

then re lay the boards and screw to the baton

again using expansion joint where the 2 substrates meet


filler foam is good and sets hard just be careful not to go daft as it does expand but can be cut with a chisel if it goes proud



andy

 

[quick draw macgraw]

Bugger already cut boards and started to fill with trumix then was going to fill up and go over with sand cement mix. Saying that the concrete edge was all over the place. Will have to see how it sets.
In the other part of room there are vinyl tiles and stuck solid, cant get them up with my SDS either was wondering whether a clean and slurry coat over would be suffice. Here are some pics.

Thanks Steve.

 

[Gazzer]

What do you intend to do with the manhole cover?

 

[quick draw macgraw]

Its flush with the floor and sealed with no movement so was going to use flexi addy over this part only with normal over the rest.

 

[grumpygrouter]

BAL SPF will go straight over secure vinyl tiles. If they are rough you could skim over with BAL Acrybase first.

Grumpy

 

[quick draw macgraw]

Is that without slurry coat Grumpy and are zinc coated screws ok for the backerboards,

Thanks Steve.

 

[grumpygrouter]

Yes Steve, no slurry coat. Not sure if zinc coating is resistant to the cement in backerboards but I would imagine it is. They use zinc to inhibit corrosion on steel exposed to the elements, but I would be guessing if I gave a resounding yes!

Grumpy

 

[DHTiling]

If you are to go over those vinyl tiles make sure they are degreased and prime with BAL bond Sbr and tiled within 24hrs.......

 

[quick draw macgraw]

Ok thanks lads.

 

[quick draw macgraw]

Hi,

for a sand cement screed do i mix 4to1 building sand to normal blue circle cement and leave to dry before going over with concrete or will sand cement screed up to desired level do?
Know how to pick my jobs for a beginner!

Cheers Steve.

 

[White Room]

No building sand you want sharp or river washed mixed semi dry as you said 4-1 to a maximum depth of 75mm. Do the concrete first then screed if thats an option for you

 

[DHTiling]

Use rapid setting cement as well this will speed up the curing process........

 

[quick draw macgraw]

Thanks,

steve.