Loft Ventilation

[cphardcastle]

Hello,

I have checked the sticky for answers but still need some clarification regarding my loft.

The situation is this: About six/eight weeks ago we had new loft insulation laid and since then have had a condensation problem in the loft.

The house doesn't have a normal pitched roof, it is a pent roof and the loft space goes from about 5ft at the front of the house to 0ft at the rear of the house.

I don't believe any ventilation exists currently but clearly I need some quite quickly.

So my questions are:

As there are no soffits as on a conventional roof how do I install vents in this roofspace?

Installing vents at the front of the house should be relatively easy as there's enough space to move about (just) from the inside but how should I install vents at the rear of the house where there is no space - will I have to remove the guttering and install from the outside?

What type of vents should I install and roughly how many will I need front and back to allow cross-ventilation; is there a rule that states X number of vents are needed for Y cubic metres of loft space?

Many thanks in advance,

Chris

 

[RedHerring2]

It sounds like the existing ventilation has been blocked by the newly installed insulation.
Perhaps the easiest solution, apart from removing any blockage is to install vent tiles/slates, but you don't mention what type of covering you have.
Normally these are installed from outside.

Recommendations of ventilation here:
http://www.roofconsult.co.uk/articles/tiling/tips28.htm

which is continuous 10mm at eaves and continuous 5mm at ridge.