Spraying Foam in the Heat: Tips for Hot Weather Application

Keep Cool and Lay That Butter
When summer hits hard, spray foam applicators have more to think about than just staying hydrated. High heat impacts everything from how your foam reacts to how your crew performs. But with the right approach, you can still produce tight seals, clean passes, and satisfied customers even in triple-digit weather.

This guide walks through key areas to help you master the craft of spraying in high temps:

• Quality checks

• Safety in the heat

• Material storage

• Equipment tweaks

• Smart spraying technique

• Job timing

• Substrate prep

• Moisture concerns

1. Safety Matters – Especially In The Heat

Summer work adds serious stress to your crew’s bodies, and PPE doesn’t help cool things down. Here’s how to protect your team:

• Build heat safety into your pre-job briefings and make sure every crew member knows emergency steps.

• Use cooling vests, portable fans, and shade breaks.

• Hydration isn’t optional. Keep cold water on-site and encourage constant intake.

• Watch for early signs of heat exhaustion: dizziness, confusion, nausea, headaches. Take them seriously.

2. Storing Your Material

High humidity means more moisture in the air and moisture is spray foam’s enemy. Foam chemistry is precise and high heat throws it off fast.

• Rotate stock to avoid old drums sitting too long in the heat.

• Keep drums out of direct sun. Use trailers with insulation or shaded storage wherever possible.

• Install AC in trailer.

• Monitor drum temps throughout the day. Stay within manufacturer specs.

3. Adjusting Your Equipment For The Heat

Hot days demand different settings.

• Keep spare parts ready to go. Breakdowns under the sun are brutal.

• Perform “bucket check” to ensure your temp settings are correct.

• Shade your hoses that are laying on the ground outside to avoid hot spots.

• Start on the lower side of temp parameters. It’s easier and faster to increase heat rather than decrease.

4. Application Techniques That Work in the Heat

5. Strategic Timing

A smart schedule helps you beat the heat.

• Watch the forecast. Consider rescheduling extreme heat days or splitting large jobs into smaller segments.

• Start jobs early in the morning while it’s still cool.

• Tackle shaded or interior areas during the peak heat hours.

• Allow longer cooling time between passes if needed.

6. Moisture Matters

Hot weather often means high humidity and that’s a problem for foam.

• Watch for condensation on cooler interior surfaces like ducts or AC-chilled walls. Use dehumidifiers or airflow to reduce risk.

• Check moisture levels in wood substrates before spraying. Keep it under 19%.

• Use closed-cell foam if humidity is extreme. It handles moisture better than open-cell.

• Consider using fans to expedite dry time.

7. Double Down on Quality Control

High heat can compromise the final product if you’re not watching closely.

• Use tools like core samples or thermal imaging to verify your install.

• Regularly inspect foam for density, cell structure, and adhesion.

• Document environmental conditions and equipment settings for every job.

8. Substrate Considerations

The surface you’re spraying onto plays a big role.

• If bonding is an issue, consider using primers to improve adhesion and prevent delamination.

• Use an infrared thermometer to check substrate temps. Avoid spraying if it’s above 120°F.

• Metal, in particular, can heat fast. Use fans, or shade to cool it down.

Lay That Butter

Spraying in the heat isn’t easy but it’s possible. With smart planning, tight technique, and a safety-first mindset, you can lay that butter even on the hottest days. And when in doubt, reach out to your IPS rep for guidance. We’re here to help you spray with confidence.