Kellyville Ridge 2155 · The Hills Shire Council
Home Additions in Kellyville Ridge: Enclosing the Alfresco
The alfresco looks like a room already. It isn't built like one.
Nearly every Kellyville Ridge home from the 2000s and 2010s has one: a covered alfresco under the main roof, off the family room. When the kids get bigger, it's the obvious place to grab another living area. Walls in, doors on, done? Not quite. The slab, the levels and the rules all need checking first.
Short answer
Can I enclose my alfresco in Kellyville Ridge?
Usually, but it needs approval and proper construction. Alfresco slabs often sit lower than the house and lack the waterproofing, insulation and footings a room needs, and habitable ceilings must be at least 2.4m. Approval is complying development if the design meets the codes, or a DA with The Hills Shire in about 11 to 15 weeks. Rawlinsons puts small additions at $1,825 to $1,965 per m².
Written and reviewed by Oliver Alameri
Licensed builder, NSW Contractor Licence 487805C · Founder, Buildana
Fact-checked
Why an alfresco slab isn't a floor slab
Alfresco slabs are built as outdoor surfaces. They're usually set a step lower than the house and fall away from it so rain drains off. Very often there's no vapour barrier underneath, because an outdoor slab doesn't need one. And termite protection may stop at the edge of the main house.
Enclose it and all of that becomes a problem. Moisture wicks up into new flooring. The floor slopes. There's a lip at the old door line. Termites have a route in under the new room.
The fixes vary: a levelling screed over a membrane, a raised floor system, or cutting out and repouring that section to match the house. The right choice depends on how far out of level it is and what the engineer finds.
- Step down from the house floor
- Fall away from the building for drainage
- Missing vapour barrier under the slab
- Termite management that stops at the old wall
An alfresco slab was poured to shed water. A living room floor has to keep it out.
Height, light and the rules around it
Habitable rooms under the National Construction Code need a ceiling height of at least 2.4m. Many alfresco ceilings meet that. Some, under a lower skillion, don't. Check before anything else.
Then light and air. A new room needs windows or glazed doors of adequate size for natural light and ventilation. And the family room behind it, which used to borrow light through the alfresco, needs to keep enough of its own.
Planning matters too. Enclosing the alfresco adds floor area and can reduce your private open space. The Hills DCP sets minimums for both. On smaller lots, it's worth checking you'll still comply.
Want to turn your alfresco into a room?
Send a photo of the alfresco, the ceiling and the join with the house floor. I'll tell you which slab fix it probably needs and how to keep an outdoor area as well.
0476 300 300Then build a new outdoor space
Most families don't want to lose outdoor living. They want both. So the usual plan is to enclose the old alfresco and add a new covered deck or pergola beyond it, often with stacking doors so the new room opens straight onto it.
Approval can go through complying development if the design meets the codes, or a DA with The Hills Shire, taking around 11 to 15 weeks.
Rawlinsons puts a brick veneer ground-floor addition of 50 to 75m² at about $1,825–$1,965/m² in Sydney, and Kellyville Ridge sits fractionally under that. An alfresco enclosure is usually smaller, so fixed costs weigh more per square metre.
Alfresco conversion checklist
Answer these before choosing windows.
- 01
Measure the step and fall between house and alfresco slab
- 02
Check whether a vapour barrier exists under the slab
- 03
Confirm termite protection covers the new room
- 04
Measure the ceiling height against 2.4m
- 05
Check open space and floor area against the DCP
- 06
Plan the new outdoor area beyond the enclosure
Enclosing an alfresco in Kellyville Ridge
Can I enclose my alfresco without approval?
Usually not. Enclosing it creates a new habitable room and adds floor area, so it generally needs a CDC or DA.
Why is my alfresco lower than the house floor?
Outdoor slabs are set lower and sloped for drainage. When enclosing, the floor usually needs levelling or repouring.
Will enclosing the alfresco make the house darker?
It can, if the room behind relied on light through the alfresco. Good glazing and skylights solve it.
Who approves additions in Kellyville Ridge?
The Hills Shire Council, or a private certifier for complying development. Kellyville Ridge's postcode is 2155.
Sources and references
Costs are from the Rawlinsons handbook with the local cost index applied; rules and timeframes are checked against the sources below.
One more room. Still an outdoor area.
Alfresco conversions and home additions for Kellyville Ridge's 2000s and 2010s homes, built properly from the slab up.