Boiling first floor in summer, unconverted Loft, epc declares a layer of 100 mm between the joists.
Anonymous user 09/03/2024 - 3.09 PM
Hello there, we bought a victorian mid-terrace in London a year ago.
Living here we discovered that when it is hot it is really difficult to sleep. The unconverted loft is super warm in summer and super cold in winter.
There is no ventilation in the loft and in the roof, and I think that when we open the windows at night, warm air continues to descend from the loft since as soon as I try to close the windows to avoid noises, the temperature immediately rises again.
Now, I just would like to know what I can do to improve the situation, maybe in the long term I could consider internal insulation in the house if this will improve the situation in summer, but I think the loft needs to be dealt with straight away.
I contacted an insulation guy and he told me that from the EPC it seems we have a layer of 100 mm between the joists and that the recommended insulation would be at 270mm. I have the feeling that this alone would not solve the problem.
What should I do? Do I need a combination of ventilation and insulation in the roof to improve the situation? In winter it is perfectly okay, the real problem is in summer since we can't sleep.
From a post here I read that a converted loft was warm because of correct insulation, so I am starting to wonder if insulating will make the situation worse. Is there someone that can help? I am not sure who should I call to have advice on this.
Edit: Today we installed 4 tile vents since I needed to do a little repair on the roof. I think the warm air is trapped in the loft and I am considering further ventilation. But as many of you mentioned, I don't understand if the problem is caused by the air rising in the evening when we sleep or by the air trapped in the non ventilated loft. Should I install a Velux, or install some turbine vents, and should I insulate? My biggest problem is during the summer. Yesterday was cold and nice outside in the evening, but as soon as we close the windows after a whole evening cooling the room down with the windows completely open, again, the temperature rose again. It is always warmer inside than outside. I don't understand if I make the situation worst by insulating more on the ceiling.
Are you a tradesperson and able to answer this question?
If you only have 100mm of old quilt in the loft my best bet is that’s your biggest issue, I’d get that topped up with some modern loft quilt to keep the heat transferring into the bedrooms 300mm would be perfect and not too expensive depending on loft space
If its a victorian property it is most likely to be built with solid walls i.e. no cavities or insulation. The loft is under insulated. Installing additional insulation is needed and you are right it will certainly stop more of the heat escaping in the winter, which is what you do want but it will also do the same in the summer (as you say) when its too hot!. So you need to look at the property more holistically to find the cause and effect and of course the solution.
The position of the property the size and energy rating of the windows, can be a source of heat gain from the sun too and because of this heat gain , hot air rises and finds its way into the loft space exacerbating the hot summer problem in the loft space.
The solid brick walls, timber floors and solid floor construction of the building will almost certainly not be insulated and so, heat conducts into the property as much as it conducts out of the building.
Imagine if the structure and fabric of the property were properly insulated, heat would neither get in or out, so in summer the property would remain cool and with a stable temperature and environment .
Introduce some modern ventilation and heat recovery system with thermo controls to the heating into the equation and bingo! You have created an amazing living environment to control your comfort and your energy and heating usage saving money in the process to py for it.
The down side of all of this is that it is not simple and does cost a fair amount of money! But money well spent on retrofitting and insulating a period home. It is neither easy or cheap to undertake but it is an incredible 'investment' in your home and the planet. This means you get a positive return for life and you add value and protect the value of the asset in the property long term.
Mike Stripling DEA
Cobalt Carbon Free
Homes for people with conscience
Increasing the loft insulation to 300mm is a good start but you could also make sure that the loft hatch is sealed when it’s closed. If it’s drafty, you could consider changing it for an air tight version.
Also check downlights and light fittings that go through the ceiling are air tight by adding hoods to them. Get an electrician to check they are correct so the lights don’t get hot.
Answered28 May 2020
1
Anonymous user
in my opinion it doesnt matter how much fibreglass you put down in your loft, your warm air rising up in your house will still pass through it, the better option could be to use a spray foam insulation between your roof joists and this will give you a gaurenteed draught free home with no chance of any mold or condensation build up. its like walking out in the snow without your hat on.
