What size caravan awning do I need? To find the correct size full awning, you must calculate your caravan’s “A-measurement.” This is the total distance from the ground, up through the entire awning rail, and back down to the ground on the other side. Once you have this measurement in centimetres (e.g., 950cm), you match it to the specific size brackets of manufacturers like Dorema (Size 12) or Kampa (Size 950).
Buying the wrong size awning is a frustrating and expensive mistake. I have seen countless caravanners wrestling with sagging canvases on windy UK pitches because they guessed their measurements or relied on an outdated owner’s handbook. Your caravan’s exact dimensions dictate what size and style of awning you can fit safely to avoid rainwater pooling and frame damage. Here is my practical guide to finding your exact “A-measurement” so you get a secure, weatherproof fit on the first try.
The “A-Measurement” Explained
Every full caravan awning on the market relies on a single crucial dimension known as the A-measurement. This is the entire perimeter of your caravan’s awning rail, measured from ground to ground. Getting this number right in centimetres is the only way to ensure your new canvas fits snugly against your caravan.
Porch, Combi, or Full Awning: Which is Right for You?
You have three main choices when selecting a new awning. A full awning doubles your living space by running along the entire length of your caravan. A combi awning offers a middle ground, while a porch awning is much smaller and quicker to pitch for weekend trips.
The Window Clearance Rule: When buying a porch awning, you must measure the flat roof section and explicitly check where the side panels will drop down. If a side panel drops halfway across an acrylic window, it will scratch the window in the wind and prevent it from opening. Keep your side panels clear of the windows, and when the temperature drops, you can easily heat the enclosed space using the best small room space heaters.
How to Measure Your Caravan Awning Rail (The String Trick)
Do not rely on the measurements listed in your caravan’s manual. If a previous owner fitted larger wheels, or your pitch is uneven, your true height will have changed.
The easiest and most accurate way to get your “A-measurement” is using the string trick. Grab a long ball of heavy-duty string and a tent peg. Peg one end of the string to the ground directly below the rear end of your awning rail. Thread the string all the way through the rail channel to the front of the caravan, and pull it straight down to the ground on the other side. Mark the string where it touches the ground, lay it flat, and measure it in centimetres. This is your exact A-measurement.
The Pitch Gradient Factor: If you regularly pitch on sloping ground, the A-measurement on the lower side will be longer. Always pack levelling ramps and a deep draught skirt to compensate for uneven UK terrain.
The “In-Between” Rule: If your measurement falls right on the boundary of two sizes, always buy the smaller size. This ensures you can tension it properly. A baggy awning will pool water and collapse under heavy rain.
UK Awning Size Conversion Charts (Dorema & Kampa)
Awning sizes vary between brands. Once you have your A-measurement in centimetres, cross-reference it with the manufacturer’s sizing table. Always double-check the latest sizing brackets on the official Dorema UK website before purchasing, as models do update.
Dorema Awning Sizes
| Measurement (cm) | Dorema Size |
| 725 – 750 | Size 4 |
| 750 – 775 | Size 5 |
| 775 – 800 | Size 6 |
| 800 – 825 | Size 7 |
| 825 – 850 | Size 8 |
| 850 – 875 | Size 9 |
| 875 – 900 | Size 10 |
| 900 – 925 | Size 11 |
| 925 – 950 | Size 12 |
| 950 – 975 | Size 13 |
Kampa Awning Sizes
| Measurement (cm) | Kampa Size |
| 788 – 812 | 800 |
| 812 – 838 | 825 |
| 838 – 863 | 850 |
| 863 – 888 | 875 |
| 888 – 913 | 900 |
| 913 – 938 | 925 |
| 938 – 963 | 950 |
| 963 – 988 | 975 |
| 988 – 1013 | 1000 |
5 Steps to Erecting Your Caravan Awning Securely
Pitching your awning properly protects both the canvas and your caravan. For additional safety tips on securing your pitch, check the Caravan and Motorhome Club guidelines.
- Thread the Canvas: Slide the canvas beading smoothly into the awning channel. Position it correctly along the roofline to clear all windows and doors.
- Assemble the Frame: Connect the roof poles to the main caravan brackets first. Once the roof structure is secure, attach the front and corner upright poles.
- Attach the Draught Skirt: Slide your draught skirt through the lower rail of the caravan and secure it with the provided ties or velcro to stop wind blowing underneath your van.
- Peg the Corners: Zip all the doors and panels shut. Peg down the four main corners first, ensuring the canvas is square to the caravan.
- Tension and Secure: Adjust the tension of all poles until the canvas is taut. Peg out the remaining rubber ladders, starting from the caravan side and working outward. To stop condensation building up on the inside of your taut awning roof overnight, consider running the best dehumidifier for drying clothes inside the space.
Once your awning is fully secure, you can focus on enjoying your trip. For more off-grid tips, read our guide on how to keep your house warm without central heating.
