Every home should have some kind of insulation to prevent heat loss and prevent too much heat gain in the summer. It isn’t just about cost, but energy efficiency and the environment. With most properties losing around a quarter of their heat through the roof, getting your loft insulation right is a good place to start. But is there such a thing as too much loft insulation?

If you live in a newer property, the answer, realistically, is that you can install as much insulation as you like. Chances are if you’re buying a new property the insulation is already as good as it can be, especially if the EPC shows high ratings. As long as you ventilate your property properly, you can have as much insulation as you like within reason. The trick with loft insulation is to balance the amount of insulation you have with the amount of ventilation necessary to prevent damp. As long as you get that balance right, you should be fine. Another thing to consider is that realistically you won’t have enough space to install ‘too much’ insulation before you run out of wall cavity, floor cavity or inside space to encroach on.

Current government recommendations are for loft insulation to achieve a depth of between 250mm and 270mm but some new properties are increasing their level of loft insulation to 300mm. Again, as long as the loft has adequate ventilation, this is fine. You may lose a little storage space but you will save money!

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Why install ‘too much’ loft insulation in the first place?

Good quality loft insulation should last decades and will pay for itself with the cash saved from heating bills. Given the relatively low cost and ease of installation of loft insulation, it should be the first place you begin if you want to make your home more thermally efficient. In this respect, it’s easy to install slightly more than recommended to increase the effectiveness of the insulation.

In winter, insulation acts as a barrier to prevent warm air generated from heating, cooking and bodies being at home from escaping your house too quickly. The more effective that barrier, the more heat you retain. In summer, your insulation does the opposite. It prevents warm air from coming in, keeping your home cool.

Loft insulation is made from fibreglass, mineral wool, sheep’s wool, hemp, recycled materials, foam and a range of materials. Different materials lend themselves to different situations and some are thinner than others for use in floors particularly. If you want to use your loft for storage, you may want to raise the level of the floor in your loft for floor insulation. A layer of insulation can be laid between joists in the floor which can then be covered over with thermally, or acoustically, insulating floorboards. As long as an air gap is left between the insulation and the floorboards then moisture should dissipate and the insulation can do its job.

Find out more about your insulation options in our Insulation buyer’s guide.



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