Insulation/vapour barrier for garden shed

igorbiscan

Ok, so this weeks project is garden shed insulation,gonna use a few 100mm rolls
of insulation and 4mm ply over that.I know that I need a vapour barrier,so two questions
1. Application- exterior wall (timber),then insulation,then vapour barrier,then plwood. Is this correct.
2.Vapour barrier- what is best? and what is an acceptable/cheaper option?
Many thanks.

heinbloed

1. Application- exterior wall (timber),then insulation,then vapour barrier,then plwood. Is this correct.

Questionmark. We don't know. Since you haven't told us if this is seen from the inside or from the outside. The consequence of material seen from a fixed point.

2.Vapour barrier- what is best? and what is an acceptable/cheaper option?

Best... cost wise? Durability? Workability? Recyability?......

The cheaper option to building an insulated garden shed is to build a garden shed. Garden sheds need no insulation.

What is the purpose of the garden shed, why insulating it?

igorbiscan

Ok thanks

heinbloed

Ok thanks for your most positive reply. why bother eh..

There can't be a "positive reply" to your sugested build-up unless the replier works in the waste industry.
The proposed build-up is fundamentally wrong. The timber at the outside (be it rough sawn planks or ply wood boards - what now?) needs to be protected against rain. Otherwise the entire structure will rot.

igorbiscan

Ok, this is an existing garden shed 1 year old,for the purpose of better protecting some gym equipment etc from the winter ahead I intend to insulate the shed on the inside,starting from the exterior wall working inwards, using rolls of insulation,then vapour barrier,then plywood for the inner finish.
I simply asked was this the correct way to layer the materials.
Is this any clearer for you?

One_More_Mile

igorbiscan wrote: »

Ok, this is an existing garden shed 1 year old,for the purpose of better protecting some gym equipment etc from the winter ahead I intend to insulate the shed on the inside,starting from the exterior wall working inwards, using rolls of insulation,then vapour barrier,then plywood for the inner finish.
I simply asked was this the correct way to layer the materials.
Is this any clearer for you?

If possible I would like some guidance on a similar related question. I have a steel roof on my wooden shed- It is full of the kids toys. Ther was heavy condensation there last year- I have since added a threadmill .There is a vapor barrier against the steel on the inside allready. So if I put up that rockwool type insulation against the vapor barrier & then some ply under that will I have issues? Or would that tinfoily bubble wrap insulation be better?

heinbloed

@ igorbiscan:

No, that is not the correct consequence. If there is no ventilated air gap between the external layer (timber) and the next layer(whatever) the timber gets soaked naturally but can't dry out. The moisture released inwards previously and ventilated away would now be stucked. Timber rot is the consequence. Effecting not only the cladding but also the load bearing timber. The nails will rust,the mineral wool will sag.

@ One_More_Mile:

If the vapour barrier is draining away the water freely, individual layers overlapping each other like roof tiles, overlaping the external wall - then the aplication of insulant under the vapour barrier will be correct. But still a ventilation gap between the insulant and the vapour barrier must be kept.
And of course a minimum slope so the droplets of condensed water can run down freely.

@ both posters:

It makes no sense to thermally insulate an unheated structure. The walls will cool down, airborne moisture will condense there. A warm and dry structure needs not only thermal insulation but a thermal energy source as well. And ventilation of course.

manus30

heinbloed wrote: »

@ igorbiscan:



@ both posters:

It makes no sense to thermally insulate an unheated structure. The walls will cool down, airborne moisture will condense there. A warm and dry structure needs not only thermal insulation but a thermal energy source as well. And ventilation of course.

can you explain then why a well insulated house is cooler in summer and warmer in winter?

heinbloed

Manus 30 asks:

can you explain then why a well insulated house is cooler in summer and warmer in winter?

I can indeed.

If you have questions concerning thermal insulation of houses please open a new thread. This thread is about garden sheds.

manus30

heinbloed wrote: »

Manus 30 asks:



I can indeed.

If you have questions concerning thermal insulation of houses please open a new thread. This thread is about garden sheds.

no need to open a new thread, this thread is about insulation. the OP asked a question about insulation and so did I.
opening another thread would be akin to opening the windows of a well insulated house during the winter, ie needless waste would result in both actions.