Of every BP344 violation we see on Philippine projects, the most common — and the most expensive to retrofit — is a ramp that is too steep. Building inspectors check ramp slope first because it's the easiest non-compliance to measure with a tape and a level: pull a string from top to bottom, drop a plumb, divide.
This guide explains the 1:12 rule exactly as BP344 requires it, walks through worked examples for the rise heights you'll actually encounter on Philippine sites (150mm sidewalks, 600mm porches, 1.5m mezzanines), and includes a free ramp slope calculator you can use right now to check your design — or someone else's.
For every 1 unit of vertical rise, an accessible ramp must travel at least 12 units horizontally. That's a maximum slope of 8.33%, or about 4.76°. Anything steeper is non-compliant — regardless of how short the ramp is, or how nice the railings look.
Enter your rise and (optionally) the available horizontal run. The calculator returns slope ratio, percentage grade, BP344 verdict, required landings, and total footprint.
The 1:12 maximum is not a Philippine invention — it's an international accessibility standard adopted into BP344's Implementing Rules and Regulations because it represents the steepest slope a self-propelling wheelchair user can climb without external assistance, over short distances. Steeper than 1:12 and the upper-body strength required exceeds what most users can sustain; gentler than 1:12 is always better, but never required.
Three things follow from this:
Every BP344 Ramp Must Satisfy All of These
| Parameter | BP344 Requirement |
|---|---|
| Maximum slope | 1:12 (8.33% grade · 4.76°) |
| Clear width between handrails | 1,200mm minimum |
| Maximum rise per single run | 750mm before an intermediate landing |
| Landing dimensions (top, bottom, intermediate) | 1,500mm × 1,500mm minimum, level |
| Handrails | Both sides, 900mm height, 300mm horizontal extensions at top and bottom |
| Handrail diameter | 33–36mm, graspable, continuous |
| Surface | Non-slip finish; contrasting strip at top and bottom edges |
| Cross-slope (landings) | ≤ 1:50 (drainage only) |
| Door swing onto landing | Must NOT reduce landing clear space below 1,500mm × 1,500mm |
Standard Sidewalk Lip — 150mm Rise
The single most overlooked ramp condition in the Philippines. Storefronts, barangay halls, and renovated lobbies routinely install a 600mm "stub" ramp for a 150mm step. That's 1:4 — three times steeper than BP344 allows.
| Required minimum run | 150 × 12 = 1,800mm |
| Number of runs | 1 (rise < 750mm) |
| Top + bottom landings | 2 × 1,500mm |
| Total footprint length | 4,800mm |
If you cannot spare 4.8m of sidewalk frontage, the correct answer is not a steeper ramp — it's relocating the accessible entrance or absorbing the level change into the interior floor finish.
Typical Residential / Commercial Porch — 600mm Rise
| Required minimum run | 600 × 12 = 7,200mm |
| Number of runs | 1 (rise < 750mm) |
| Top + bottom landings | 2 × 1,500mm |
| Total footprint length | 10,200mm (10.2m) |
This is the case most architects discover too late. A 600mm finished-floor-level above grade — extremely common in Philippine commercial buildings designed for flood clearance — requires a 10-meter accessible ramp envelope. Plan it on the site plan, not the architectural detail sheet.
Mezzanine or Half-Storey — 1,500mm Rise
| Required minimum run (slope only) | 1,500 × 12 = 18,000mm |
| Number of runs | 2 (rise > 750mm requires intermediate landing) |
| Intermediate landing | 1 × 1,500mm |
| Top + bottom landings | 2 × 1,500mm |
| Total footprint length (straight) | 22,500mm (22.5m) |
This is when you switch to a switchback or a lift. A straight 22.5m ramp is rarely feasible. A switchback (U-turn at the intermediate landing) cuts the footprint roughly in half but requires a wider landing — 1,500mm × the ramp width sum. For full-storey rises (≥ 3,000mm), an accessible lift is almost always more practical than a compliant ramp.
From the projects we audit and the BP344 violations our team has corrected on retrofit jobs across Philippine commercial buildings:
| # | Mistake | Why it fails |
|---|---|---|
| 1 | Slope between 1:8 and 1:10 | Looks gentle enough to a walking inspector. A tape measure or smartphone level catches it instantly. |
| 2 | No landing at the door | Door swings onto the ramp slope; wheelchair user cannot hold position while opening the door. |
| 3 | Single run for > 750mm rise | No intermediate landing — rest stop is a code requirement, not a convenience. |
| 4 | Handrail on one side only | Common on ramps next to a wall. BP344 requires both sides regardless of wall proximity. |
| 5 | Smooth glazed tile finish | Looks premium, fails the slip-resistance requirement — especially when wet from Philippine rains. |
What it costs to fix after pouring: in our experience, retrofitting a non-compliant concrete ramp on a finished commercial building runs ₱45,000–₱180,000 per ramp, depending on whether the slab needs to be extended or replaced. Designing it correctly from day one costs nothing extra.
Ramp slope is one standard. The BP344 Reference covers the full accessibility envelope — every dimension you need for permit-ready drawings, with illustrated diagrams for ramps, parking, toilets, corridors, doors, pools, and signage.
The most expensive BP344 problem is discovering it at the permit stage. AEDO designs the accessibility envelope — ramps, parking, toilets, corridors — before the floor plan is finalized, so compliance is never a retrofit.
If you've inherited a too-steep ramp on an existing public building, you have three options ranked by cost and complexity:
What is not a fix: adding more handrails to a steep ramp, putting in non-slip strips, or posting a "Assistance Required" sign. Inspectors reject all three.
Is 1:10 ever acceptable?
No. BP344 sets 1:12 as the absolute maximum. Some older references mention 1:10 for "ramps less than 200mm rise" — this allowance was removed from current IRR practice and is not honored by Philippine building officials.
Does the 1:12 rule apply to driveways?
No. Vehicular driveways are not pedestrian accessible routes. But the section where a driveway crosses a sidewalk — the curb ramp — must comply with BP344 cross-slope and gradient limits.
What about ramps inside parking garages?
The vehicle ramp itself is exempt. But any pedestrian ramp from the parking level to the lobby — including the path from accessible parking slots — must satisfy 1:12.
Do temporary or event ramps need to comply?
Yes if the event is open to the public. Modular aluminum ramps sold in Philippine hardware stores are often pre-engineered to 1:12 — check the manufacturer's slope spec before renting.
Where can I get a sealed ramp design?
Any licensed Philippine architect or civil engineer can produce one. AEDO's design-build team includes BP344-sealed ramp details in every commercial project we deliver — at no extra design fee.
Where can I find a free BP344 reference with all accessibility dimensions?
The AEDO BP344 Reference is a free visual guide covering 40+ accessibility standards with dimensioned diagrams — ramps, accessible parking, PWD toilets, corridors, doors, pool decks, and signage. No login, no paywall. Built by Filipino engineers and used by architects across the Philippines for permit-ready accessibility design.
Can AEDO audit my existing drawings for BP344 compliance?
Yes. Send your architectural drawings with an inquiry to AEDO and we'll provide a written BP344 gap assessment within 48 hours — marking up ramp slopes, parking dimensions, toilet layouts, and corridor clearances before you submit to the building official. This pre-submission audit is free for projects we subsequently design or build.
This guide covers ramps. The AEDO BP344 Reference covers everything else — parking, toilets, corridors, doors, pool decks, and signage — with the dimensioned diagrams architects use directly in permit drawings. 40+ standards, fully illustrated, zero cost.
| Standard | This Guide | BP344 Reference (free) |
|---|---|---|
| Ramp slope (1:12 rule) | ✓ | ✓ |
| Ramp landings & handrails | ✓ | ✓ |
| Accessible parking dimensions | — | ✓ |
| PWD toilet compartment layout | — | ✓ |
| Door clear width & hardware | — | ✓ |
| Corridor & passageway widths | — | ✓ |
| Pool deck & transfer wall | — | ✓ |
| Tactile & wayfinding signage | — | ✓ |
| Dimensioned diagrams (40+) | — | ✓ |
No login. No paywall. Built by AEDO's engineers and used by architects and developers across the Philippines for permit-ready accessibility design.
A correct ramp slope is one checkbox on a 40-item BP344 compliance list. The hard part is designing all of them into a building that still functions beautifully — before the permit is submitted, not after. AEDO's design-build process starts with the BP344 envelope and works the architecture inward, so compliance is never a surprise.
Already have drawings? Upload them with your inquiry and we'll mark up the BP344 gaps before we discuss any project scope.