Concrete floor right up to exterior brick wall?

perc

Hi I am raising the flooring in my dining room which used to be a garage so has a concrete floor. Reasons for raising the floor are:

1. To insulate against the cold
2. To make the level the same as the rest of the house

I have pulled the old laminate flooring up which had been laid directly onto the wooden floor which a thin insulating sheet under it. I can see that where the concrete floor meets the brickwork at the back of the house there is a gap of about 3mm - 5mm. Should this gap be there or would it be best if I were to fill it in with either a sealant or concrete?

Thanks in advance for any advise that you may be able to give

macduf

A weatherproof sealent will be sufficent.

dampdaveski

hi,
what are you raising the floor with?
concrete or laying a wooden floor on top?
If you're concreting you should seal the gap between the new concrete and the house wall or even better grind a mortar joint out and point the edge of your damp proof membrane into the wall

perc

dampdaveski wrote: »

hi,
what are you raising the floor with?
concrete or laying a wooden floor on top?
If you're concreting you should seal the gap between the new concrete and the house wall or even better grind a mortar joint out and point the edge of your damp proof membrane into the wall

Hi I am raising the floor using wooden battons with chipboard boards on top

dampdaveski

Hi,
ok grind the joint out using a grinder, clean the joint out using a vacuam cleaner and apply a polysulphide sealent, ask your local uilders merchants about sealant for a construction joint
after you fit your battens it will be a very good idea to fit some insulation into the floor.
Make sure you allow for proving some ventilation into your newly formed sub floor, ie stick an air brick or two to both ends of the room
good luck!

perc

dampdaveski wrote: »

Hi,
ok grind the joint out using a grinder, clean the joint out using a vacuam cleaner and apply a polysulphide sealent, ask your local uilders merchants about sealant for a construction joint
after you fit your battens it will be a very good idea to fit some insulation into the floor.
Make sure you allow for proving some ventilation into your newly formed sub floor, ie stick an air brick or two to both ends of the room
good luck!

Would it be best to run the battens across the room across the width or length - was planning the width but this could restrcit the air flow across them i guess?

27col

When raised the floor of the garage that I was converting to a flat. I was going to fix the chipboard sheets onto battens. However, the Building Inspector said to me that what I proposed was not necessary. What he told me to do was to lay the 50mm polystyrene insulation slabs on top of the concrete. Then lay a polythene sheet on top of the polystyrene. Then lay the boards down loose on top of the polythene. What we did was to stick the boards together by putting PVA glue on the tongue and grooved edges. After doing this to a few sheets the weight became such a solid mass that there was no way the floor would move. This has been down since 1992 and there has been absolutely no problem. This solution saved me lot of work fixing and levelling all the battens that I was proposing to use. The concrete under the insulation slab was covered with a thick layer of Synthaproof. This is a tarlike product using for water proofing walls and floors. There is no airflow of any kind under the floor. It is just 5 layers. Concrete, Synthaproof, 50mm polystyrene, sheet of polythene, and boards stuck together on top. It all seems to work alright.