Buyer guide
Flood barrier sizing guide measure openings, pick heights, choose a format
Most flood barrier RFQs stall on missing measurements. This guide explains how to measure openings, choose a sensible barrier height and pick the format that fits — so your quote comes back accurate the first time.
- Measure clear width at the narrowest point
- Choose height from local flood information plus margin
- Match format to opening type and storage space
- Copy the checklist into your RFQ
1. Measure the opening
Measure the clear width between the two reveals or jambs at sill level, mid-height and top; use the smallest figure. Note the sill: is it level, sloped or uneven? For plank systems and flood gates, also record wall depth beside the opening for mounting channels. For door barriers, record the jamb material and whether a threshold protrudes.
2. Choose a barrier height
Height should come from local flood information — past high-water marks, flood maps or your engineer — plus a margin. As rough planning ranges: door barriers for shallow surface water (tens of centimetres), stacked plank systems when higher protection is needed (plank by plank to the required height). We quote the height you specify; we do not advise a rated height.
3. Pick the format
Use the table below as a starting point. Homeowners with standard doors usually choose residential door barriers; wide garages and driveways need plank systems or gates; long, irregular runs suit inflatable or water-filled tubes; gaps and secondary openings take absorbent sandbag alternatives.
4. RFQ checklist
- Opening type and quantity of each size
- Clear width (min of three measurements) and sill condition
- Target water height and margin
- Mounting: permanent channels, temporary clamps, freestanding
- Finish, branding and packaging requirements
- Required standards or documentation (we confirm what can be provided)
Send it via the inquiry form.
Format selection matrix
| Opening | Typical width | Suggested format | Notes |
|---|---|---|---|
| Single house door | ~70–110 cm | Adjustable door barrier | Tool-free, retail friendly |
| Double / patio door | ~120–250 cm | Plank system or inflatable tube | Check mounting depth |
| Garage door | ~240–500 cm | Plank system with posts / garage dam | Dam for runoff only |
| Driveway / yard opening | Custom | Hinged or lift-in flood gate | Fixed frames required |
| Long perimeter | Many meters | Inflatable / water-filled tubes | Needs flat ground |
| Gaps, vents, secondary openings | Small | Absorbent sandbag alternative | Single use |
No certification claimed by default. We do not claim FEMA, Miami-Dade NOA, UL, ASTM or any other approval, rating or test result. Products are built to customer-specified standards; test reports can be provided on request where available.
Frequently asked questions
How do I measure a door for a flood barrier?
Measure clear width between jambs at the bottom, middle and top and use the smallest number; note threshold height and jamb material.
How tall should a flood barrier be?
Base it on local flood information plus a margin. We build to the height you specify and do not provide rated heights.
Can one barrier fit several door sizes?
Adjustable door barriers cover a size range per SKU; plank systems and gates are made to each opening.
What if the sill is uneven?
Note it on the RFQ with photos. Uneven sills may need a sill plate or a different format.
Related pages
Measurements ready?
Send the checklist and we will propose formats and a quote.