How to Measure for a Custom Retractable Awning

Getting your measurements right before purchasing a custom awning is one of the most important steps in the whole process. And here’s the good news: it’s more straightforward than most homeowners expect. A little preparation up front means your new awning fits perfectly, shades exactly where you need it, and looks great for years to come.

Whether you’re transforming a backyard patio into a true outdoor living space, shading a front porch, or covering a commercial storefront, the approach is largely the same. This guide walks you through exactly what to do before you contact an installer — from the tools you’ll need to the specific numbers you’ll want to have ready.

Why Getting the Accurate Measurements Matters

A custom awning is built to your exact specifications. Unlike off-the-shelf options, a made-to-order awning from a company like Designer Awnings is manufactured based on the dimensions you provide. Once it’s built, there’s no simple way to adjust the width or projection after the fact.

For Pennsylvania homeowners, where temperatures swing from humid summers into cold, snowy winters, a properly sized awning also plays a real role in your home’s energy efficiency. An awning that’s too narrow won’t adequately shade a window or door, which affects how cool or warm your home stays inside. One that projects too far without proper pitch can collect rainwater or accumulate snow load. Getting the numbers right from the start protects your investment and ensures your awning performs the way you need it to, season after season.

Inspect the Installation Area

Take a few minutes to really look at the space where the awning will be mounted. This step gets skipped more often than it should, and it causes headaches down the road.

Check the mounting wall for anything that could complicate the install: gutters, downspouts, exterior light fixtures, electrical boxes, security cameras, or HVAC vents. On older homes, also check the condition of the fascia board or soffit. If the surface is rotted or structurally weakened, it will need to be repaired before an awning can be safely anchored there.

Then look outward. Consider the path the awning will take when it’s fully extended. Trees, overhead wires, fencing, and nearby structures like garage walls or pergola posts can all limit the usable projection. Understanding the physical boundaries of your space helps you land on the right dimensions before you ever contact a supplier.

Homes in the Lehigh Valley region vary widely in lot size and exterior configuration, so this inspection step is especially worth doing carefully. Designer Awnings offers in-home consultations specifically to help homeowners identify these variables before committing to dimensions.

The Two Core Measurements: Width and Projection

Every awning is defined by two primary numbers.

Width is the horizontal measurement of the area you want covered, from one side to the other. For a patio or deck, measure the full span you want shaded, not just the door or window opening. A common guideline is to add a few inches on each side beyond the target area to ensure complete coverage. Your installer can advise on the right amount of overlap based on your specific setup.

Projection is how far the awning extends outward from the wall when fully open. The deeper the projection, the more shade you get at ground level. Projection also needs to fit your available outdoor space without extending into walkways, landscaping, or neighboring structures.

For reference, the retractable awnings offered by Designer Awnings can be built up to 40 feet wide and project up to 14 feet 8 inches from the wall. Most residential installations fall well within those limits, but knowing those boundaries helps when planning larger covered areas.

Check for Level and Determine Mounting Height

After confirming the width and projection, measure and record the height at which the awning will be mounted. Mounting height affects pitch, which matters for two practical reasons: proper water runoff and usable headroom beneath the awning when it’s extended.

Retractable awnings should have a slight downward pitch toward the outer edge, generally between 5 and 15 degrees, depending on the model. This ensures rainwater runs off the fabric rather than pooling on top of it. Water that sits on awning fabric for extended periods accelerates wear and can stretch the material over time.

Use your spirit level to confirm the mounting surface is plumb and even. Even a small variance on the wall can translate to a visible tilt in the finished awning, particularly on wider installations. If there’s any question about the levelness of your wall, flag it for your installer before the job begins.

📣 Ready to Move Forward? Get a Free In-Home Estimate.

If you’ve taken your initial measurements and want expert guidance on next steps, the team at Designer Awnings offers free in-home estimates for homeowners across Berks, Northampton, Lehigh, Monroe, Luzerne, Carbon, Lackawanna, and Schuylkill Counties. A professional measurement visit takes the guesswork out of the process entirely.

Request Your Free Estimate →

Understand Which Awning Type You’re Measuring For

Not every awning installs the same way, and the type you select can influence which measurements matter most.

Retractable awnings mount to a wall, soffit, or roof and extend outward on a motorized or manual arm system. These require clearance in front of the mounting wall and enough wall space to accommodate the hardware brackets on either side of the fabric span.

Courtyard awnings are freestanding or post-supported structures designed to cover large open areas such as courtyards, pool decks, or event spaces. For these, you’ll need the overall footprint dimensions of the area to be covered, as well as post placement options.

Roof-mounted awnings attach directly to the roofline and are often used in locations where wall mounting isn’t feasible. These require additional measurements related to roof pitch and overhang depth.

For businesses, commercial shade structures may have different load requirements and signage considerations that affect sizing. Commercial installations also often need to comply with local zoning ordinances around signage and projection over public walkways.

Mistakes to Avoid

Even careful homeowners make measurement errors. These are the most common ones worth watching for:

Measuring only the door or window opening. The awning should cover the space you actually use, not just the wall opening.
Forgetting to account for obstructions. A gutter positioned right where a mounting bracket needs to go can require relocating the entire installation point.
Measuring projection from the floor instead of from the wall. Projection is always measured from the mounting point outward, not from the edge of your deck or slab.
Overlooking load considerations. Mounting into stucco, EIFS, or deteriorated wood requires special anchoring. Make sure your installer knows what they’re working with.
Skipping local permit research. Some Pennsylvania municipalities and HOAs have rules about awning size, color, or placement. Check with your local building department before finalizing dimensions, especially for projections that extend over a public right-of-way.

Once you have your measurements, your installer will benefit from as much context as possible. Plan to share:

Your recorded width and projection measurements
The intended mounting location (wall, soffit, or roof)
The mounting surface material (brick, wood siding, stucco, vinyl, etc.)
Any obstructions noted during your inspection
Photos of the space from multiple angles
Your preferred use case: shade only, rain protection, year-round use, etc.

Fabric selection also plays a role in how the awning performs in your specific conditions. Designer Awnings offers a wide range of awning fabrics — all UV-resistant and designed for outdoor durability. Discussing your climate exposure, preferred aesthetics, and color preferences during the consultation helps narrow down the right choice.

For retractable models, additional features like wind sensors, motorized controls, and LED lighting options from the accessories line are also worth discussing during your consultation.

A Note on Professional Measurement

For most standard installations, a homeowner with a tape measure and a helper can gather solid preliminary dimensions. That said, final measurements before manufacturing should always be confirmed by a trained installer. Small errors that seem insignificant in planning — a quarter-inch variance on a bracket placement, a slight grade in a concrete slab — can affect how the awning sits, operates, and drains.

Designer Awnings handles professional measurement as part of the free estimate process, so there’s no need to worry about submitting final specs on your own. The goal of your initial DIY measurement is to understand your space well enough to have a productive first conversation.

Regulations and Safety Standards Worth Knowing

Pennsylvania building codes vary by municipality, but most residential awning installations don’t require a permit if the structure is attached to the home and within certain size thresholds. Homeowners in HOA communities should review their association guidelines before purchasing, as restrictions on color, material, and projection are common.

For commercial installations, local zoning codes often govern how far an awning can project over a sidewalk and what signage is permitted on the valance. Designer Awnings has experience navigating these requirements across the counties they serve and can advise on compliance during the consultation process.

All Sunesta retractable awnings installed through Designer Awnings are TÜV Rheinland tested and certified. The retractable line also carries Miami-Dade County Approval for wind resistance, one of the most rigorous certifications in the awning industry. For Pennsylvania homeowners who deal with summer storms and unpredictable high winds, that level of certification means real peace of mind.