Brick veneer vs double brick: the differences and how to tell

Same look, different building

Two brick homes can use different structural systems. In brick veneer, a timber or steel frame carries the roof and floors and a single outer leaf of brick, about 110 mm thick, acts as cladding. In double brick, also called cavity brick or cavity masonry, two leaves of brick stand either side of a cavity and the masonry itself carries load. Older homes, mostly before the mid-twentieth century, may instead have solid brick walls: two or more bricks thick, bonded together with no cavity. YourHome also describes reverse brick veneer, with the brick on the inside and a lightweight cladding outside.

The terms people use, and what they actually mean

How to tell which system you have

No single clue settles it, because renovations, linings and additions can disguise the original construction. Combine several of the checks below, starting with the easiest, and treat plans or a building inspection as the confirmation where the answer affects a decision.

Why wall thickness alone does not decide it

A typical veneer wall adds up a 110 mm brick leaf, a cavity of about 40–50 mm, a 70–90 mm frame and the internal lining. A typical double brick wall adds two 110 mm leaves, a cavity of about 30–50 mm and internal plaster. Both commonly finish somewhere around 250–300 mm, so a measurement at a door or window narrows the possibilities without settling them. Thickness is more useful for spotting a change between the original house and an addition. Midland Brick describes double clay brick as two leaves with a 30–50 mm cavity.

Location matters more than most buyers expect

In Western Australia, the Urban Development Institute of Australia reports that housing construction in Perth is dominated by double brick, while other capitals more commonly use framed construction. So 'double brick' in a Perth listing is the expected default, while the same words on an eastern-states house built after the 1960s deserve confirmation.

Why the difference matters to you

Reading cracks

Cracking reads differently in each system. In brick veneer, the outer leaf is a weather skin and may crack as that leaf moves; the frame behind it needs its own assessment. In double brick, a cracked leaf may be carrying load. In solid brick, the wall is the structure. Width, direction, location, associated distortion such as sticking doors, and change over time remain central in every case. Use the full pattern in cracks: structural or cosmetic, then confirm the wall system.

Damp and the cavity

Cavity walls are designed to let some water through the outer leaf and drain it back out. Masonry construction guidance requires weep holes in the external leaf of cavity and veneer walls at centres not exceeding 1200 mm, sitting directly on a cavity flashing that sheds water outward. Solid brick walls rely on their mass and a damp-proof course instead, and behave differently when wet, which is covered in the period homes guide. For persistent internal damp, use damp and moisture in your home.

Comfort and insulation

Double brick brings thermal mass; brick veneer relies on insulation within the frame, commonly the full depth of the studs. Thermal mass stores heat, while insulation slows its transfer, and their value depends on climate, orientation, shading and where the mass sits. Retrofitting insulation into a double-brick cavity is possible but changes how that cavity handles moisture, so ask the installer how drainage and ventilation are maintained.

Renovating and altering

Altering brick veneer means working with a frame, which can still carry substantial roof and floor loads. Altering double or solid brick can mean cutting into walls that hold the house up, needing new lintels, engineering and a support sequence. Establish the load path before anyone talks about removing a wall, using the process in planning a renovation.

Common misreads

A house may contain more than one wall system

A solid-brick front house can meet a framed rear addition. A rendered upper floor can conceal a different system from the ground floor. A garage may be single-leaf brick. 'Double brick' in an advertisement should become a room-by-room or elevation-by-elevation record where the distinction affects the purchase, the renovation budget or the insurance description. The era guides help here: interwar, post-war, 1980s–90s and 2000s onward.

Brick veneer has structural responsibilities even though it is not normally the main roof-supporting structure: the outer leaf needs adequate support at openings and restraint back to the frame. Conversely, calling a house double brick does not establish that every internal wall is loadbearing, that both leaves have identical roles, or that the roof framing is free of timber-pest risk.

Follow the cavity and the water exit

The outer face sheds most rainfall while some water reaches the space behind it. The question is where that water drains and whether it can reach the inner construction. YourHome's wall-system guidance explains why the drainage route and the layers behind the external finish matter. Painting a brick face, raising garden beds or paving over the weep holes, or sealing visible openings without understanding their function can trap water rather than stop it.

A crack that appears only in an accessible outer leaf narrows the observation; it does not prove the rest of the building is unaffected. Bulging, loose masonry, displaced supports or progressing distortion need prompt professional assessment, with access kept clear of any potentially unstable area. Ask the inspector to distinguish what was seen from what remained concealed, as set out in how to read a building and pest report.

Acoustic privacy is a separate question

Masonry is often quieter between rooms and from outside, but a solid-feeling wall does not establish acoustic performance on its own. In apartments and attached homes, sound also travels through windows, doors, floors and service penetrations. If noise matters to the purchase, visit at relevant times, ask about complaints and alterations, and consider specialist acoustic advice for a consequential unresolved issue.

What to establish before altering a wall

Before budgeting for an opening, ask which wall supports what, how the loads reach the ground, whether supports have already been altered and what temporary works will be required. Request plans, previous engineering details, permits and photographs of concealed work, and identify services in the proposed opening. A report that labels the house 'brick veneer' has not necessarily assessed that particular wall for removal. Record the difference in the renovation brief.

For older solid masonry, ask whether proposed repairs suit the existing bricks and mortar. Hard cement repairs or impermeable coatings on soft historic brick can trap moisture and accelerate decay. Use the period-home guide for compatible-repair questions, and the red flags by era guide for what typically goes wrong in each period.

Worked example: one crack, two possible structures

Illustrative reasoning example, not an inspected property. Two listings show a similar stepped crack at a window. One is a 1970s Melbourne house with drawings indicating brick veneer; the other is a 1990s Perth house described as double brick. The photographs support a statement about the crack's visible pattern. They do not establish its cause, the condition of the lintel above the opening or whether movement is continuing.

For the first home, check the relationship between the outer leaf, the frame and the window support, and look inside for matching lining cracks or sticking doors. For the second, the masonry is structural, so establish the lintel arrangement and load path first. In both, dated photographs and inspection of associated distortion are useful. The construction system changes the investigation brief; it does not, by itself, decide whether a repair is minor or structural.