Standard SG24 Sizes at a Glance

The CA-FIRE SG24 series is the manufacturer’s model code for the internal fire hose cabinet range. Every SG24 cabinet shares the same 700 mm height and 240 mm depth; only the width changes across the four standard sizes. Consistent depth means that a mixed-size installation on a single corridor — for example an 800 mm cabinet next to a 1800 mm combined station — will present a uniform 240 mm wall projection, which simplifies wall detailing and finishing.

At a glance, the four sizes and their primary uses:

Full Dimensions Table

Complete SG24 dimensions in millimetres and inches, across the four standard sizes. Use this table as the primary reference when dropping a cabinet block into a CAD drawing or spec document.

Weights are approximate and apply to standard 1.0–1.2 mm painted carbon steel body without equipment installed. Stainless steel variants are approximately 5–8% heavier; recessed variants are approximately 10% lighter because they omit the back panel where the cabinet integrates with the wall cavity.

Rough Opening Table (Recessed Installations)

For recessed flush-mount installations, the rough opening in the wall framing is slightly larger than the cabinet body itself to give installers shim room during seating. The factory-fitted trim ring on the cabinet front covers the gap, so minor framing tolerance (up to about ±10 mm) is forgiving.

The table below lists the rough opening dimensions for each SG24 size in the recessed configuration. Use these numbers when coordinating with the framing contractor or drawing the wall framing plan. Note that the 800 mm size (SG24A65-J) is not offered in the recessed configuration — the cabinet is too small to justify the wall cut and framing labour for most projects.

The minimum wall cavity depth of 260 mm is the single most important number in this table — it rules out standard 100 mm and 150 mm metal stud walls in the fully recessed configuration. If your project uses standard 150 mm stud walls, either specify thicker studs at cabinet locations or use surface-mount cabinets instead. CMU block walls of 200 mm or more are the easiest to recess into because the block coursing can be adjusted to suit the opening.

Matching Cabinet Size to NFPA 14 Class

The cabinet size you need depends on the standpipe class the hose station serves, not on building type alone. NFPA 14 defines three classes (I, II and III) based on who operates the hose; each class has different internal equipment and requires a different minimum cabinet size. The table below shows the recommended SG24 size for each class. For a full explanation of the NFPA 14 classes, see our Class I, II, III explained guide.

Practical sizing rule of thumb: start with the class required by your local code, then add 200–400 mm of cabinet width for every additional accessory (second extinguisher, spare nozzle, hose reel, fire axe, spanner wrench). An 800 mm Class II station with nothing but a valve, hose and nozzle can accommodate a small extinguisher; add a 10 lb extinguisher and a spare nozzle and the 800 mm cabinet is full — step up to 1600 mm.

Dimensional Differences Between Variants

The CA-FIRE SG24 range is offered in three engineering variants: tempered glass front, stainless steel, and recessed flush-mount. Most dimensions are identical across variants (that is the whole point of a standard range) but there are three small differences worth knowing before you commit a size to a drawing.

Three small size differences between variants

• Tempered glass door width is approximately 3 mm inset from the cabinet face to allow for the glass frame — this affects nothing functionally but shows on precision drawings.
• Stainless steel body uses 1.0–1.2 mm 304/316 sheet which is the same thickness as painted carbon steel, so external dimensions are identical. Only the weight differs (304 stainless is about 5% heavier than carbon steel of the same thickness).
• Recessed 800 mm size is not offered. The smallest recessed cabinet is 1000 mm wide. This is because an 800 mm recessed cabinet requires the same framing labour as a larger one, and the small footprint rarely justifies the fit-out cost. For applications where only 800 mm width is available, use a surface-mount glass-front or stainless cabinet.

Internal Clearances — What Fits Inside

External dimensions are only half the sizing question. The other half is internal clearance — how much usable space remains inside the cabinet after accounting for the door frame, hinges, hose rack mounting brackets, and the standpipe connection at the rear. The table below gives approximate internal working dimensions for each SG24 size.

Internal depth is the most constrained dimension and the one that surprises first-time specifiers. A 240 mm external depth leaves only about 200 mm of usable internal depth after the door frame, back plate and fittings. Check the depth of your planned hose rack, extinguisher and valve before finalising the size — a 10 lb extinguisher is typically 150–180 mm deep at its widest point, leaving 20–50 mm of clearance, which is enough but not generous.

Wall Depth and Cavity Requirements

Wall compatibility is a separate conversation for surface-mount versus recessed installations. Surface-mount cabinets only need a solid wall thick enough to anchor the cabinet body — as little as a 100 mm masonry block or a reinforced stud wall will do. Recessed cabinets, by contrast, need a wall cavity at least 260 mm deep, which rules out several common wall types. The table below summarises compatibility.

Metric / Imperial Conversion Reference

For projects specified in imperial units, the SG24 metric dimensions convert cleanly to round-ish imperial values. The table below lists exact conversions for the dimensions most likely to appear in a drawing or spec sheet.

On a U.S. imperial drawing, it is common to round the width to a nearby convenient number — for example, calling out a 1600 mm cabinet as “63 inches” on the drawing. The rounding is within tolerance for cabinet positioning but the actual manufactured dimension is still 1600 mm. Always reference the metric dimension in the spec text even if the drawing shows imperial, so the manufacturer and the framing contractor work from the same number.

Custom Sizes and Special Requests

The four SG24 standard sizes cover the vast majority of commercial fire hose station installations. For projects that require something outside the standard range, custom sizes are available to order — typical reasons to go custom include:

• Heritage retrofits where the existing wall opening is a non-standard size from an original installation 30 or 40 years ago and the replacement cabinet must fit the same opening.
• Unusual equipment such as combined stations with a breathing apparatus cylinder, a rope escape system or an oversized accessory panel that does not fit the standard 700 mm height.
• Architectural requests where the designer wants a cabinet proportioned to match wall panelling modules, door heights or other visual elements of the finished corridor.
• Export market variations for countries where local fire codes require specific cabinet dimensions different from the CA-FIRE standard range — for example, some Middle Eastern and Latin American jurisdictions specify a 650 mm height instead of 700 mm.

Custom cabinets typically add 4–6 weeks to the standard lead time because of additional tooling and QC steps. Minimum order quantities apply for some custom configurations (usually 10 units for non-standard dimensions, 1 unit for standard sizes with non-standard accessories). Email sales with your project specifications — a drawing, the target dimensions and the equipment list — and we confirm feasibility and lead time within one business day.

Frequently Asked Questions