Could we insulate the attic ourselves to save money this winter?

We can never seem to get our entire home to the desired temperature. The ground floor gets close to the correct temperature but upstairs is always off; it’s often too cold or too hot.
We’ve been told by friends that insulating the attic can make a difference. We are hoping to improve this before the winter months. Is this something you would recommend and, if so, what type of insulation makes most sense for a terraced home?
As we don’t want to spend a lot of money, is this something we could do ourselves?
Your question is particularly important as we enter the winter months. It is an issue that can be easily resolved to increase the comfort level of your house.
I assume, based on your description above, the issue of the house being too cold or too hot is seasonal whereby the upstairs is too cold in winter and too hot in the summertime. This is due to a lack of insulation providing a barrier to trap heat within the first floor in winter and to mitigate against heat seepage from the attic void to the first floor during the warmer summer months when direct sunshine causes heat build-up in the attic.
As a starting point, you should have a look around the attic and ascertain what level of insulation is in place at the moment, if any. If there is no insulation in place you will be able to see the plasterboard of the ceiling or the laths from older lath and plaster ceilings (depending on the age of the property). If some insulation material is in place, you should consider how it has been fitted and the condition it’s in.
With older properties that have some insulation in place, we often find that it is not performing as it should. Usually that is because it’s in poor condition, well compressed or has been pulled out of place in several areas. In this instance, you should consider taking out any existing insulation, disposing of it and installing new Earthwool insulation to a depth of 400mm. Newer properties may have some insulation that may simply need to be added to; in that case you should measure the depth of existing insulation and increase accordingly.
Fitting the insulation correctly is important and should be done in a two-layer process with the layers of insulation laid criss-cross over each other to break the side-by-side joints between the rolls of insulation when they have been rolled out. When fitting the insulation, you will also have to ensure that ventilation is maintained to the attic void. You may notice that vents are in your soffit externally which provide ventilation in the attic void and this is typically to mitigate condensation occurring within the attic. That ventilation will need to be maintained and you should ensure it is not blocking any vents around the perimeter of the roof. If there are no vents to the attic, these will need to be provided and you should seek advice from a chartered building surveyor in that regard.
With regards to fitting the insulation, this is something a sure-footed DIY-inclined homeowner could do themselves with the appropriate personal protective equipment (it’s a fairly dusty job and the material can irritate) but you would need to be cognisant of the method of installation and maintaining ventilation as described above. You would also need to be confident you can make your way around a confined attic void while standing or kneeling on narrow timber ceiling rafters.
While fitting the insulation is not an overly specialised task, there is a lot of merit in engaging a contractor who would typically carry out this work on a daily basis. They will inevitably be best set up to complete the task and will fit the insulation quicker and possibly to a better standard than a homeowner who may be learning on the job. But that is your call.
Aidan McDonald is a chartered building surveyor and a member of the Society of Chartered Surveyors Ireland
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