Wall insulation and Vapour layers?

[robbie1977]

Hi,
I have recently replaced all the plaster in my lounge room and installed 1.5 batts in the walls. Unfortunately i wasn't aware of vapor layers when installing the batts. To be honest all the posts i have read refer to weatherboard. Can any one tell me what to expect from not installing them. My house was built in 1956 and is solid clay brick.

[monkeyrelish]

Hi Robbie,

I think we need a bit of clarification... when you replaced the plaster was this the hardplaster skim over the brickwork? or is the house constructed using solid masonry external walls and timber frame with plasterboard internal walls?

If the walls are internal then you shouldn't worry too much about vapour/moisture/condensation, as these vapour barriers/membranes are generally needed externally as weather boards don't always seal totally from the weather and due to rapid heat loss/gain I think that a greater amount of condensation is developed as a direct result of this.

That's not to say that you don't get moisture with solid masonry or even brick veneer, you can get plenty.

[SilentButDeadly]

You'll be fine....although I'm mildly surprised to hear of a brick veneer home in 1956.

If you are refering only to internal walls in a full brick house.....then you don't need a vapour barrier at all. Only in external walls.

[uidaa]

Plaster is fine for indoor. For outdoor, you've could use cement board

[robbie1977]

You'll be fine....although I'm mildly surprised to hear of a brick veneer home in 1956.

If you are referring only to internal walls in a full brick house.....then you don't need a vapor barrier at all. Only in external walls.

You might be right about the surprise! I didn't realize it may have been rare, but every time someone comes out they expect it to be double brick. The house was build as the Olympic village for the athletes. Bit of a dodge area but on the way up. Anyway i digress, it is brick veneer and i have laid insulation in between the internal plaster and the brick work which is an external wall. The house doesn't have any damp problem and the wall i did is mostly out of the weather (east facing).

Thanks for all you responses, so will i need to membrane the rest of the house to be safe? and exactly what am i looking for? i assume bunnings would know what I'm after. Thanks again for all your help, one day i hope to return the favor for a puzzled DIY'ER

[fubar]

dont rely on bunnings try taits timber hardware let your fingers do the walking

[ausdesign]

The Vapour barrier [ RFL ] would normally be used to keep the batts within the the stud work to ensure restriction of air movement.
I doubt if you will have problems from moisture although it sounds like it could be possible if the batts are touching the inner face of the brickwork.
RFL also adds around R0.4 to your insulation levels in your particular construction type.

[robbie1977]

The Vapour barrier [ RFL ] would normally be used to keep the batts within the the stud work to ensure restriction of air movement.
I doubt if you will have problems from moisture although it sounds like it could be possible if the batts are touching the inner face of the brickwork.
RFL also adds around R0.4 to your insulation levels in your particular construction type.

thanks for the advise, I will use the rfl for the rest of the house, insulation benifits are always good. hope for the best with the old insulation and fingers crossed it wont get damp

Thank you to everone who replied, has assisted greatly

[sundancewfs]

Vapour barriers are used in the states where they have extemes of temperature, ie -30c outside and warm inside. The temp difference causes condensation like you wouldn't believe!