Insulation: what the experts had to say

A couple of weeks ago we gave you all the chance to quiz the experts on all things insulation as part of our Facebook Live chat with Will and Chad at SuperFOIL.

There was a big response, with dozens of questions coming through in advance and on the day about insulation, getting your home weather ready, and of course the government’s Green Homes Grant, which is available until March 2022.

You can still catch up on the lively discussion between SuperFOIL’s Managing Director Will Bown and National Sales Manager Chad Bragg, and our very own Trade Manager Rob Martin – but for anyone who missed it, we’ve pulled together some of the highlights.

Chad – the unofficial chair of the chat – pointed out that the grant is generating a lot of questions for the team at SuperFOIL, so a lot of questions were around this. But there was also a lot to say about being more sustainable and saving money – and how to select the right project for the job at hand.

Let’s dive in!

When it comes to cavity walls, if you can’t or don’t want to go for external options, and don’t want to lose space inside – what are the options for retrofitting insulation?

Rob: I would say get a specialist contractor to do this. Insulation, such as EPS beads, will be ‘blown’ into the cavity from the outside. This will make a huge difference to the comfort levels and heat loss in the home.

Will: You will need to make sure, if you’re organising this through the Green Homes Grant, to find a certified TrustMark installer and a fully-trained installer. Companies like SuperFOIL offer training in installation, so it’s essential to find someone who is both qualified and competent.

I rent – my property is cold in winter, and my landlord is being unhelpful! What can I do?

Chad: We should say firstly that landlords have a responsibility to help. Landlords should invest in their properties to ensure that they can continue to rent out their property in the future.

Rob: Yes, landlords have to produce an EPC certificate, so it’s worth checking whether this is in place. If this falls short, it is the landlord’s responsibility to sort this issue out.

Will: But there are a few things you can do. Check air tightness – use draught excluders and letterbox seals, as well as kits for windows to create a ‘double glazing’ effect for older houses. Radiator insulation kits ensure heat returns to the room, and use things like rugs and heavy curtains to keep heat out.

Chad: Once you’ve checked the boiler and bled the radiators, radiator kits prevent heat from getting sucked into the wall – and they’re inexpensive and easy to install.

Will: We do a bubble foil insulation kit which is fitted behind the radiator and reflects heat back from the radiator into the room rather than heating the wall. The kit includes the roll of bubble foil, which you cut to size, and then stick the foil with double sided sticky pads to the wall.

I’m building a garden office but I don’t know what kind of insulation to use. Help!

Will: Outdoor buildings are not well sealed, and don’t benefit from heat mass – so this is an important question.

Chad: The type of building matters here. If it’s a timber frame building, then SuperFOIL is ideal as you can staple the product straight to the timber frame. If it’s a wooden floor, you should drape SuperFOIL products over the floor joists before the floorboards are fitted and that will give you a very good performance – and it is the thinnest, highest performing option.

Will: It also depends on what you’re using it for, if you’ll be using the garden office for hours a layer of 19+ on the walls will get you close to building regulations. But if you’re only using the office for an hour or two at a time, use bubble foil – it’s cheaper, and it will keep heat in shorter term.

I have a flat roof that is in good condition – is there any insulation that can be retrofitted on top of a flat roof?

Will: This is not a very common option; you’d need to pull back the felt as a first step. You could fit new foam board then replace the waterproofing on top, which is what often happens with schools. We offer a solution: remove the felt, use SuperFOIL then batten, then new OSB over the top – and then re-felt over the top. Our technical team can run some calcs for you to make sure you achieve the right U-values. I would recommend the SF40 or 60, but this depends on the structure.

Chad: So, as Will says, the key thing is check out what’s already there and then contact the SuperFOIL technical team.

SFTV is really popular – what makes it special?

Chad: What makes it unique is that it’s a high-performance vapour barrier. It has foil finish on both sides, so it’s reflective on both sides and it is fully reinforced so it’s a really tough material – almost impossible to rip. It was used on a round the world hot air balloon trip, which is testament to the thermal performance and the strength of the material. All that, and it’s one of the most cost-effective materials of its type – so that’s why it’s so popular!

I’m looking for loft insulation – I currently have 100mm, is that enough? I don’t want to use mineral wool.

Rob: Well, traditionally you would use mineral wool, but if they don’t like that then there are other options.

Chad: There are two different scenarios whether it’s the pitched roof section, or the floor – with two different product types. If you want to use the loft space, then mineral wool is sometimes impractical. Sheep’s wool is an option if you don’t want the irritation of mineral wool.

Will: Yes, glass wool on the floor is the cheapest option, but it will mean that you lose some loft space. If you insulate the floor, it will save money on heating bills as you won’t be heating the loft. But if you want to keep the loft itself warm, if you’re storing things in the loft, then insulating the pitched roof section is the right choice.

Chad: Some items don’t keep well in extremes of temperature, which is an important consideration in the UK too – by insulating the roof, you’re regulating the temperature which is better if you’re storing things like photos or furniture. Insulating at the pitched roof level, look at a SuperFOIL product that you can staple into place which offers a clean and dust-free solution. You can use SuperFOIL on the floor level, by stapling over the joists in the same way.

Any questions?

If you still have questions about insulation, the Green Homes Grant, or SuperFOIL, there’s lots of information on and on the Insulation Superstore.

What’s more, you can still watch the full video on the Insulation Superstore Facebook page – and feel free to ask us any questions you have by leaving a comment or sending us a direct message, and we’ll make sure our experts get back to you with a response as soon as possible.

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