Comparison
This is not a spec grid; it is a graph walk. Each candidate below carries the same verdict language as every other surface on the site, and the ordering reflects how sensibly each one fits the three answers you have given us.
01 · Home
Solid or early-cavity walls, a bay-fronted ground floor and a loft that is nearly always the room worth insulating first
Solid brick walls, sash windows, single-skin extensions round the back and party walls that quietly ration the ways heat can leave
Cavity-wall construction, generous glazing, a detached plot that opens the archetype up to the sun in three directions
Single storey with the loft immediately overhead
Thick permeable walls, small deep-reveal windows and a listing sensitivity that constrains every intervention
Neighbours on three or four sides borrow and lend heat
Timber-framed or cavity-walled with hung tile above the ground floor and thermal bridging that quietly runs the annual bill
One-and-a-half storeys with living space pushed into the roof
A tight fabric, generous glazing and an MVHR system that is either the archetype's biggest advantage or its most-neglected liability
Three storeys stacked over an integral garage
02 · Room
A small volume with one occupant contributing sensible and latent heat for eight hours
Thin insulation between rafters, a hot roof above and rooflights that resist proper shading
Glazed walls and roof deliver enormous solar gain by midday and equally enormous heat loss overnight
One occupant plus screens contribute meaningful heat across a working day
The largest habitable volume in most homes and rarely on its own thermostat
03 · Problem
Why is my house too hot in summer, and what actually fixes it?
Why is the bedroom too hot to sleep in, and what would actually help tonight?
Why is this room cold when the rest of the house is fine?
Why is water forming on my windows and walls, and what should I do about it?
Do I have a damp problem, and if so, which of the three kinds?
Where is the cold air coming from, and what stops it?
Why does the air in this room feel stale, and what would actually help?
Where is the noise getting in, and what actually reduces it?
Why are the bills higher than they should be for a house this size?
The three answers you have given us do not resolve to a candidate we would honestly stand behind. Try relaxing one axis; the graph is small on purpose, and an empty result is usually more useful than a padded one.
Why we have reached this conclusion
If we change our mind about a unit anywhere on the site, it changes here on the same day. The ordering is a graph walk, not a spec sort; the tier lines against your chosen home and room come from the same Suitability Matrix that appears on every product verdict.
A comparison that will not tell you when a unit is not for you is not a comparison; it is a menu. The tier that reads Not this one is doing as much editorial work as the tier that reads Clear fit.