Pack 25 Roofing Felt Lap Vent Stops Loft roof Condensation / Attic Space Ventilation Airflow

I bought these as we had a problem with condensation in the loft of our new house. The en-suite bathroom had been vented directly into the loft (not easy to see as at other end of loft from hatch) and was first noticed when I went up to the loft to get the Christmas decorations down. This coupled with non breathable old style plastic roofing liner meant that I then found puddles of water everywhere and water running down the liner and trusses. After fixing the main cause of the condensation (venting the bathroom outside!!) we then needed to increase the airflow to dry out the loft and stop condensation occurring again. Initially I removed the insulation that was stuffed into and blocking the soffits, however I then had a choice to either try these or put vents into the soffits. These were the much easier (but more expensive) install so I thought they would be worth a try. I placed one in every other truss gap in the loft alternating between as low as I could reach and 3/4 of the way up the roof. I was not expecting great results as the loft was very wet, however two weeks later and it was nearly bone dry. Very impressed with the results and saved me from climbing ladders and drilling holes.Obviously it may not be suitable for all situations, but if you have non breathable liners like myself and getting to the soffits to install vents is awkward it may well be worth a try. Also if you have another root cause of condensation like me, then fix that first!Pros:Seems to provide good airflowEasy to installDoes the job requiredCons:Expensive for what they are.

I had no problem with damp in my roof space until I fitted a floor in the loft and also we had a shower pump installed which created a lot of steam in the bathroom. Both these factors then contributed to condensation forming in the loft, I went in to the loft to get the Christmas decorations only to find everything wet, the floor had water on it, the felt was dripping, it was really bad and the wooden rafters were also very wet - not good. I read the reviews on this product and thought for the sake of £62 it was worth a try before calling in a roofing expert. It took me around 15 minutes to install 25 vents - very easy indeed. I inspected my loft one week after installation and now it is completely dry, no damp or condensation whatsoever. Even all the water that had accumulated on the floor has dried up in just 7 days. I have seen comments saying that the vents are expensive for what they are - just some moulded plastic which is true but then who cares? - It's what they do that counts - and they solved my roof problem 100% without having to call in experts and saved me a fortune, I'm sure. I just ordered a second pack as the box of 25 fitted about half of my roof space, so I will finish the job off now with another box - I cant recommend these enough.

Item made out of thin plastic but still fit for purpose. Very easy to fit in the felt overlaps, just slides into place & is held in place with it's plastic clips. You can feel air movement straight away if the wind is in the right direction.Fitted early Jan 2017, so far seems to work very well at completely clearing the condensation.I bought 25x (to fit a 5 bedroom house with a L shape loft) but really only needed to fit 20x to get the loft totally clear of condensation. If need be I'll fit the rest later. I suppose it depends how bad the condensation is to how many you need & how you space them.You can check out these on the manufacturers web site which gives product info & fitting PDF files plus a Manthorpe G630 vent installation video.Very useful info.A recommended purchase if you suffer from condensation &. have a felt roof lining in which you can slide these vents.

Have a large loft so overall have installed 50, - it certainly does allow fresh air into the loft and within a few days the moisture did start to disappear and so far everything has remained dry, - although the weather has turned milder.Very easy to fit and these are worth a try before considering other options such as venting tiles.

Slips into felt joins easy. May not go all the way in if the battens are close but still ventilate. Be careful with older bitumen based roofing felts as they can easily tear, fit on a warm day when the felt is softer and be gentle.

Hadn't been in the loft for a while, got the Christmas decorations down & realised that the box they were in was wet - shone a torch up into the rafters to investigate & realised that the felt on pretty much all of the inside of my roof had moisture on it, which was so bad in parts that it was dripping. On further investigation, some of the wood was wet, and some of my lagging had gone black. Not good to find.A bit of googling quickly told me that my loft had a moisture problem, probably not helped by the fact that my kids stay in the shower for hours & never open the windows, and my radiators are constantly covered with washing that's drying off (all that steam needs to go somewhere).But what to do? Firstly, make everyone open the windows when in the shower. Open all the vents on the UPVC window frames, open windows to ventilate the house, make sure loft hatch lid is properly sealed (mine wasn't), and install some of these in your roof felt - I was a bit sceptical to begin with, but after installing them a few months ago (and generally increasing ventilation around the house) my loft is now bone dry. I ended up using the whole box which may have been overkill but they definitely done the trick.Well worth the money, highly recommended.