Prefabricated steel buildings are renowned for their durability, affordability, and adaptability, making them a popular choice for everything from warehouses and workshops to aircraft hangars and churches. However, steel has one notable drawback: it conducts and retains heat more effectively than many other building materials. Without proper precautions, steel buildings can quickly become uncomfortably warm, making them inefficient and even unusable in extreme heat.

Thankfully, with the right strategies, you can make your building more comfortable and energy-efficient all summer long. Below, we explore the most practical methods to keep your steel building cool during the summer.

Prioritize Proper Insulation

Insulation is the crux of climate control for any building, and steel structures are no exception. Good insulation keeps indoor spaces cooler during summer and warmer in winter by preventing heat transfer between the building’s exterior and interior. Insulation will also drastically reduce your reliance on air-conditioning, lowering monthly utility costs this summer.

Spray foam insulation is sometimes used on prefabricated steel buildings, as it adheres tightly to metal surfaces and effectively seals small cracks and crevices. This dual function promotes optimal energy efficiency.  However, it is not recommended because most manufacturers void the warranty if spray foam is used as it restricts the movement of the building components and causes moisture to be retained against the metal panels which can cause rust. 

Fiberglass batts are another common insulation option. Lightweight and easy to install, batts are a cost-effective choice for wall and roof insulation. However, the batts need a tight fit to avoid air leaks.

If durability is your top concern, use rigid foam panels. This form of insulation is excellent for its high-resistance thermal control, and you can install the panels on various sections of your structure.

Adding insulation to a preexisting steel building can be a bit more challenging because retrofitting may involve removing wall panels or adding them to crawl spaces and ceilings. That said, retrofitting is still usually well worth the investment. That said, take the time to inspect the existing insulation for wear or damage every year so it stays in good condition.  Do check with the manufacturer to get recommendations and make sure your warranty is not accidentally voided. 

Install a Cool Roof

A structure’s roof impacts how much heat a building absorbs, particularly in hot, sunny climates. Steel roofs, in particular, can quickly become hot to the touch under direct sunlight, which then radiates heat into the interior. Installing a cool roof is a highly effective way to counteract this heat buildup.

The design of cool roofs reflects sunlight, allowing the roof to absorb less heat than standard roofing materials. One popular approach to implementing this design is applying reflective coatings directly on the roof. These coatings use advanced materials that bounce solar radiation away from the building, keeping the roof cooler.

If yours is a refabricated steel structure, then you have the option to use roof panels with integrated reflective properties, which offer a long-term solution with minimal maintenance needs.

The advantages of a cool roof extend beyond improved temperature control, though. By minimizing heat absorption, cool roofs also increase the longevity of the roofing material itself. Rapid heating and cooling cycles cause expansion and contraction, which can weaken steel roofs over time. A cool roof mitigates this stress.

Optimize Ventilation Systems

Ventilation systems keep the air inside your steel building fresh and cool. Without proper airflow, heat can build up and stagnate, making the structure uncomfortable for everyone inside. Steel buildings can benefit from multiple ventilation strategies to regulate indoor temperatures and eliminate trapped hot air.

One go-to solution for many steel building owners is to install ridge vents along the highest points of the roof. The vents allow hot air to escape naturally, taking advantage of the fact that warm air rises. Exhaust fans provide additional support by actively pulling warm air out of the building. Proper placement of windows and intake vents on opposite walls can also promote cross-ventilation, allowing cooler air to flow in as warm air exits.

While ventilation creates a foundation for managing heat, pairing it with an air-conditioning system offers even more control. While some warehouses might be OK without them, community-focused structures, like steel church buildings, absolutely need a functioning AC unit.

AC systems work exceptionally well in buildings with specific cooling needs, such as workshops with heat-generating equipment or storage facilities housing sensitive materials. To maximize their performance, consider choosing cooling units with high Seasonal Energy Efficiency Ratio (SEER) ratings, as these ACs operate more efficiently and offer long-term energy savings.

Incorporate Effective Shading

Adding shade to a steel structure is a simple yet powerful tool for reducing heat exposure. By blocking direct sunlight, shading cools the building’s exterior and the surrounding environment. This cooling strategy can be incredibly versatile, depending on the layout of your building and its location.

For instance, awnings or overhangs above entryways and windows can block sunlight while still allowing airflow. These additions are particularly effective for rooms with large sun-facing windows, as they reduce indoor heat gain. Shade screens are another lightweight option that works well to deflect sunlight and minimize glare.

Landscaping also provides natural shading solutions. If you haven’t yet built your steel structure, select a well-shaded spot. Otherwise, plant deciduous trees strategically around your building so the foliage blocks sunlight during summer while letting light pass through when the leaves shed in winter. Shrubs and climbing vines can help too, effectively shading lower sections of the building.

Consider Light-Colored Paints

Here’s another method you can use to keep your steel building cool during the summer: paint the structure a lighter color. Darker colors like black or deep blue tend to absorb more sunlight, converting it into heat. Lighter tones, however, reflect more sunlight, keeping temperatures lower inside your building.

When repainting a steel structure, consider shades like white, cream, beige, or soft gray. These colors help with temperature regulation and give the building a clean, modern look. Select paints designed for metal buildings for the best results, as these formulas include more reflective properties and will adhere to the surface more easily.

Repainting is an excellent opportunity to increase your building’s energy efficiency while also refreshing its appearance. Whether your building is undergoing routine maintenance or a full-scale renovation, choosing light-colored or reflective finishes is an easy yet impactful upgrade to implement.