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Q&As
Do I need to carry out extension and insulation upgrades at the same time?
I am planning an extension and wish to use the facility provided by Building Regulations Part L ‘Whole Dwelling calculation method’ clause 4.6. The area-weighted U-value of my extension is worse than required, due to the amount of glazing incorporated. At the same time I intend to upgrade the roof insulation to the existing dwelling and this U-value gain would outweigh the shortfall in the extension. My question is whether I have to carry out both the extension and the insulation upgrade at the same time, or can I proceed with the insulation upgrade prior to commencing the extension at a later date?
2 Answers
Hi John,
Thanks for your question. I have asked one of our experts for comment and will get back to you as soon as possible.
Hi John,
Yes you can upgrade your roof insulation at any time and commence the extension at a later date. The only benefit of doing both at the same time might be a slight reduction in costs. It’s not clear from your message what the roof insulation entails – if it’s just top up of loft insulation then this is not a difficult task but if the roof is being substantially altered and scaffolding is required then the saving would be more significant.
Best regards – Nigel Griffiths (Build It Sustainability Expert)