The right material for an open attic floor, and the cheapest route to R-50.
Both reach R–50 and both are blown from a machine outside through a hose. The choice is about the attic, not about ideology.
| Cellulose | Blown fibreglass | |
|---|---|---|
| Density | Higher — resists air movement within the layer better | Lower — does not load an old ceiling |
| If it gets wet | Absorbs, and must be replaced | Sheds water, often dries out |
| Made from | Recycled paper, borate treated | Glass, largely recycled |
| We choose it when | Standard truss attic, sound ceiling | Light ceiling, known leak history |
Depth markers go in before the blow and stay afterwards, so the depth can be verified by anyone.
Blown material needs somewhere to sit. A cathedral ceiling or a flat roof has no open floor, and those are dense-pack or foam jobs surveyed individually. Blowing into a bay you cannot see the far end of is how voids happen.
Cellulose settles a predictable amount, which is why it is installed above the target depth to a specified coverage. Fibreglass settles very little.
It is borate-treated and tested to the same standards as any other insulation. It chars rather than flames.
Related
Book an attic check
You get the depth, the tier, the dollar figure and the photographs, whether or not you go ahead with us.
