In-house
Envelope.
The permitted development envelope is the volume you are allowed to build within before anyone needs to ask permission. Envelope is the engine we built to find it. Most practices check those rules by hand, against legislation that changes every year and reads like it was written to be argued over. We encoded them directly.
The unusual part is the input. Envelope reads the BIM model and takes heights, projections and boundary distances from the geometry itself, rather than trusting a dimension somebody typed onto a drawing. If the model says the eaves are 3.1m, the model is what gets tested.
It never overstates.
Where the facts are contested, or a drawing cannot prove compliance, it says so and recommends a certificate. It will not hand back a pass it has not earned.
That is deliberate, and it is the same standard the drawings are held to. A tool that tells you what you want to hear is worse than no tool, because you act on it.
Envelope is used on our own projects first. If you run a small practice or a BIM team and want to talk about how it works, get in touch — that conversation is a different one from a householder enquiry.
Your project
Tell us what you want to build.
Send photographs, the address and a description. You get a written view of what looks likely, which route applies, and what would need checking properly before you spend anything.