Loved our conservatory at our old house (I know they aren't that popular on Mumsnet).
We are considering either a Conservatory with a glass roof, or a sun room with a supalite roof.
Got a quote on a 2.5 x 3.5m glass - £9k
or 3.5m x 3.5m supalite roof £11k.
Does anyone have experience of a supalite roof? Are they a good alternative to an extension?