Permission
Most home installations count as permitted development, but older properties are where the exceptions sit.
- Listed buildings. Drilling through a wall or fixing a unit to the outside usually needs listed building consent from Guildford Borough Council. Allow for the application time in your plans.
- Conservation areas. Permitted development rules are tighter. A unit on a wall that faces the road is the most likely thing to need permission.
- Surrey Hills National Landscape. Much of the countryside around Guildford is protected, and the council looks at how visible new equipment would be.
- Article 4 directions. Some streets have removed specific permitted development rights. The council’s planning pages list where these apply.
Not sure if your house is listed?
Search the National Heritage List for England on Historic England’s website, and check Guildford Borough Council’s conservation area maps. The surveyor can help you read them.
Walls and pipe routes
Period walls are usually solid brick, flint or stone rather than cavity. That changes how the pipes get from room to garden.
- Drilling. A diamond core drill makes a clean round hole with little vibration. Thick walls simply take longer.
- Following existing routes. Old chimney breasts, airing cupboards and unused flues often give a hidden path between floors.
- Lath and plaster ceilings. These are fragile, so pipes are usually routed through the loft or along skirting rather than chased into ceilings.
Hiding the outdoor unit
The outdoor unit is what neighbours and planners notice. A few placements tend to work well on older houses:
| Position | Why it works | Watch for |
|---|---|---|
| Rear ground level | Out of sight from the road | Distance from the rooms upstairs |
| Side return | Common on Victorian terraces | Airflow in a narrow passage |
| Behind a parapet or flat roof | Invisible from the street | Safe access for servicing |
| Garden enclosure | A slatted timber screen blends in | Keeping enough space for airflow |
Choosing indoor units
High ceilings, cornicing and picture rails don’t suit every unit. Options that work in period rooms include:
- Slim wall units in white or silver, placed above a door or on the plainest wall.
- Floor consoles, which sit low like a radiator and leave the cornicing untouched.
- Ducted grilles from the loft, for top-floor rooms where the loft is accessible.
At the survey
- Planning status checkedListed, conservation area, Article 4 or none.
- Routes walked throughWhere pipes and cables can run without disturbing original features.
- Placement agreedIndoor and outdoor positions you are happy with, before any price is fixed.
Tell us about your house
The estimate takes a few minutes, and the survey covers the planning side.