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Wheelchair Ramps & Level-Threshold Doors: A Practical Guide for Safer, Easier Access
Wheelchair Ramps & Level-Threshold Doors: A Practical Guide for Safer, Easier Access
Need easier access into your home? This guide explains how wheelchair ramps and level-threshold doors work together to create safer, step-free entryways. We’ll cover recommended widths, ramp gradients, drainage details, and which door types best support a flush threshold in UK homes.
Part M of the Building Regulations "Access to and use of buildings" has been around for a good few years now. New houses are built to help with access to your home if you are in a wheelchair. Wider openings, level threshold doors and wheelchair ramps help access your home. Inside your house wider internal doors and corridors, a downstairs toilet big enough for a wheelchair, lower level light switches etc were all designed in, to improve the lifestyle of a disabled person or indeed to help with old age, something we cannot avoid forever.
Quick Answers
- Level threshold = max 15 mm upstand with any upstands above 5 mm chamfered to ease wheel overrun.
- Common ramp gradient for dwellings: 1:12 (rise:run), with handrails recommended when steeper than 1:20.
- Doorway clear opening typically needs ~850–900 mm for wheelchair access.
- Most sliding and many bifold systems struggle to achieve full weather-rated, flush thresholds—plan drainage carefully.
What Is a Level-Threshold Door?
A level-threshold (sometimes called a flush threshold) is the lowest, smoothest door entry you can achieve while still controlling weather and heat loss. The UK definition allows no more than a 15 mm rise across the threshold, with minimal upstands and gentle chamfers to avoid jolts for wheelchair users and people with limited mobility.
Why it matters
- Prevents trip hazards
- Enables independent entry for wheelchair and mobility-aid users
- Reduces strain for prams and trolley users
- Future-proofs the home as needs change
Accessibility in New vs Older Homes
Newer homes are generally designed around Part M principles (e.g., wider doorways, easier circulation, downstairs WC). Older properties often need retrofits: wider openings, level thresholds, and ramped access are the most common upgrades we deliver across Hampshire and surrounding areas.
Choosing Doors That Work with Level Thresholds
Most modern front and back doors (e.g., high-quality composite, uPVC, timber, or aluminium entrance doors) can be specified with compatible cills and threshold details for step-free access.
Note on patios and bifolds: Many sliding and bifold systems don’t carry the same severe-weather rating at ultra-low thresholds. If you want that flush look, factor in external drainage to protect against wind-driven rain.
An example of wheelchair access threshold on a composite door
Getting Drainage Right (Critical for Flush Thresholds)
Where thresholds are nearly flush, drainage is non-negotiable. Best-practice guidance includes:
- Provide an external landing sloped 1:40 to 1:60 away from the door.
- Keep water falling in one direction—avoid cross-falls.
- Discharge to a drainage system or permeable drain.
- Add a drainage channel between landing and threshold (and again where ramp meets landing).
- Consider extra drainage in exposed locations.
Ramp Design: Recommended Gradients & Handrails
For most residential settings, a 1:12 gradient is widely used (1 unit rise per 12 units run). Where gradients exceed 1:20, install handrails on both sides for safety and assistance.
Doorway Widths That Work
For wheelchair users, aim for a clear opening around 850–900 mm. Remember: the “frame size” of older doors (often ~925 mm external) doesn’t equal the usable opening. What matters is clear passage width after accounting for the sash, hinges and furniture.
Popular Solutions We Fit
- Step-free composite entrance doors with low thresholds
- Flush external cills engineered for drainage
- Retrofitted ramps in concrete, brick, or modular systems
- Wet-room and internal door widening as part of a broader accessibility upgrade
Contact us
Ready to explore the best Part M compliant level threshold doors for your home? Contact our experts today for a free survey and quotation
Wheelchair door threshold FAQ's
Older housing in the UK before the new regulations were typically around 925mm wide. This measurement was the external frame width, so really offers no guide of how easy it would be to get a wheelchair through the door. The Disability Discrimination Act (DDA) regulations mandate that doorways in accessible buildings should be wide enough to accommodate individuals with disabilities. The minimum clear opening disabled door width for DDA compliance is typically around 850mm to 900mm. In essence the clear opening should be wide enough for a wheelchair user to access a property.
15mm - The maximum upstand of 15mm upstand at the door threshold with additional sloping transition elements, such as a small internal ramp and external cill, may be provided either side of the upstand. The maximum slope on ramps and cills should be 15 degrees
1:12 - Best practice is to have a slope of one in twelve. This standard aligns with the Building Regulations and recommends that ramps have a maximum gradient of 1:12 meaning for every 12 units of horizontal distance, there is 1 unit of vertical rise. The provision of handrails on both sides of the ramp for gradients steeper than 1:20
Mark Pearce is a highly experienced specialist in the double glazing industry, having built his knowledge from the ground up through hands-on experience in installation, manufacturing, sales, and business management. Beyond his role at KJM, Mark is a keen blogger, writer, and traveller, often sharing insights on the latest innovations in the home improvement industry.
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