In short, open-cell foam is softer, more affordable, and allows moisture to pass through. Closed-cell foam is denser, stronger, and provides more insulation per inch.

Open-cell foam is around R-3.6 to R-3.9 per inch. It works well when there's plenty of room for thicker insulation. Since it's vapor permeable, the wall or roof assembly can dry out if moisture gets in.

Closed-cell foam is around R-6 to R-7 per inch, so you get much more insulation in less space. It also helps control moisture and can make the surface it's applied to more rigid. The downside is that it costs more.

Closed-cell foam is usually the better choice when space is tight or moisture is a concern. It's commonly used around rim joists, in crawl spaces, on basement walls, below grade, and in some unvented attics.

Basically, if you need the highest R-value possible without using a thick layer of foam, closed-cell is usually the way to go.

Open-cell foam makes sense when you have enough room for a thicker layer and want to keep costs down. It's often used in interior walls, vented attic floors, and soundproofing projects.

It's also softer than closed-cell foam, which helps absorb sound. That makes it a popular choice between bedrooms, bathrooms, offices, and other rooms where noise matters.

Open-cell foam is an industry-standard option for roof decks because it can make roof leaks easier to detect. Since water can pass through the foam, a leak is more likely to show up as a wet spot or ceiling stain.

Closed-cell foam does not allow water to move through as easily. If a roof leak occurs, moisture may become trapped between the foam and the roof deck. By the time the problem is discovered, it may have already caused mold, rot, or damage to the roof deck.

That doesn't mean open-cell is always the right choice for every roof. Climate, local building codes, roof design, and moisture control all matter.

Choose closed-cell foam when space is limited, moisture is a concern, or you want extra strength. Think rim joists, crawl spaces, basements, and places where every inch counts.

Choose open-cell foam when you have more room, want better sound control, or want the assembly to dry more easily if it gets wet. It's also usually the less expensive option.

When it comes to roof decks or other moisture-sensitive areas, have the full assembly checked before deciding. The right foam depends on more than just the R-value.

Cold weather can throw off your temperatures and lead to bad foam. The biggest issue is when the A-side and B-side are not at the same temperature.

If one drum is warmer than the other, the material can flow differently and cause off-ratio foam.

Keep both drums warm and at the proper temperature before you leave for the job.

Don't wait until you get to the site to start warming cold material. In winter, properly conditioned drums make a big difference in how the foam sprays.

Don't only rely on the temperature shown on the machine.

Pay attention to the hose temperature and material temperature at the gun. Also give the primary heaters enough time to recover between passes, especially when you're spraying a lot of material quickly.

Even if the foam is warm, the surface you're spraying onto can still be too cold.

Spraying warm foam onto a freezing-cold roof deck, wall, or other surface can cause poor adhesion, condensation, and bad foam quality.

Always check the substrate temperature before spraying.

Check the foam manufacturer's minimum temperature requirements.

If the substrate is below the minimum, warm the area before spraying or wait until conditions improve. Trying to force the job in temperatures that are too low can lead to problems you'll have to fix later.

Keep it simple: keep the A-side and B-side at the proper temperature, and condition the drums before you get to the job. Watch the temperature at the gun, not just the machine display, and give the heaters time to recover between passes. Always check the surface temperature before spraying. If it's below the manufacturer's minimum, warm it up or wait.

Good winter foam starts with good temperature control.

Start with how much foam you expect to spray in a normal day and how quickly you need to apply it. A contractor spraying a set throughout the day has a different workload from someone trying to spray that same set in a short, continuous run. Daily volume gives us a starting point, but the pace of the job matters too.

Choose a proportioner that can handle your daily spray volume while working at a moderate capacity. If you're constantly pushing a smaller machine to its limit, you're putting more strain on the equipment. Going with a more powerful machine lets it handle the same workload without working as hard, which helps reduce wear and extend its life. For example, if you normally spray one set a day, we want a machine that can comfortably handle that amount at your usual spraying pace. The goal is to keep the machine working at a medium level instead of overworking it every day, so it lasts longer.

Not always. A large machine can easily handle one spray gun, but a smaller machine may struggle with two. If the machine can't keep up, both guns may lose pressure and performance.

Spray foam equipment uses a lot of power, especially the primary heaters and heated hose. If the electrical supply is too small, the machine may struggle to maintain temperature, leading to off-ratio or soft foam.

Every Reactor has a maximum supported heated-hose length, and your setup needs to stay within the limit for that model. Within that limit, choose enough hose to reach the work you actually do. Check the hose's compatibility with your equipment as well; length alone doesn't tell you whether a hose is suitable.

Extra reach is useful when a job needs it, but unnecessary hose adds electrical resistance to the heating circuit. Past a certain length for your model, that resistance can reduce the current reaching the far end of the hose, which under-heats the material and shows up as poor mixing and spray quality, not just a slower warm-up. On a generator-powered rig, the added heating load can also mean more fuel use. Think about where you normally park and how far you need to reach inside the building. That gives you a more useful starting point than automatically buying the longest setup your machine supports.

Use our parts diagram to locate the component you need, then match it to the part number shown. Start with the correct equipment model so you're looking at the right diagram. Two parts can look very similar in a photo and still belong to different assemblies.

If you already have a part number, use that to help narrow the search. If the diagram doesn't make the answer clear, contact us with the model and serial number and, if possible, a photo of the part or the area it came from. You don't need to guess from a picture. We can help you work through the diagram and identify the correct replacement.

Talk with one of our equipment professionals about how you'll use the setup. Bring the details that affect the choice: your current machine, typical daily spray volume, the reach you need, and what you want to improve. If you're replacing something, tell us what you like about it and what gives you trouble.

We can use that information to help you compare suitable options. With a gun, compatibility and day-to-day servicing matter. With a reel, the hose you need to carry and the space available in the rig matter. With a package, look at what is included and how it fits the rest of your setup. A lower upfront price is only helpful if the equipment meets your actual needs. Ask about equipment and we'll help you find the right fit.

For the generator, our sizing target is roughly 80% of its continuous rated output under the rig's normal working load. For example, a 20 kW continuous-rated generator at 80% load is supplying about 16 kW. That leaves headroom, but the final choice also needs to account for equipment startup demands and the generator manufacturer's specifications. List the equipment that will run at the same time so the generator can be sized around the whole rig.

For the compressor, look at the airflow it can supply at the pressure your equipment needs, along with its duty cycle. Duty cycle describes how much of a defined period the compressor is rated to work. A piston compressor rated for 50% duty needs equal working and rest time within the manufacturer's specified cycle. Check the actual model rather than assuming every piston compressor has that rating.

Rotary screw compressors are commonly designed for continuous operation, with many rated for 100% duty. A blanket rule of 95% on and 5% off does not apply to all of them. Share the compressor model and the air requirements of your equipment with us, and we can help you match the capacity and duty rating to the way you spray.

A standard gun rebuild is usually same day if you drop it off in the morning and the seal kit is in stock, which it normally is. Ship-in guns are typically turned around within one to two working days of arrival. If we find something beyond a normal rebuild we call you with a price before we go further.

It depends entirely on the fault. Straightforward items — heaters, transducers, pump packings, hose ends — are often same day or next day. Board-level electrical faults and anything needing a part we do not stock depend on the manufacturer. We will always give you a realistic time once we have diagnosed it, not an optimistic one.

Yes, and plenty of customers do. Pack it clean and dry, include a note with your name, phone number, the fault and your return address, and send it to the Brooklyn or Bridgeport address above. Call or use the form first so we know it is coming and can watch for it.

Please do what you reasonably can — purge it and wipe it down. We understand cured foam happens; that is part of the job. But a gun arriving full of wet, uncured chemical is a handling hazard for our technicians, and we may have to charge extra cleaning time.

Ask us when you book — it depends on the machine and the fault. If the repair goes ahead with us, diagnostic time is normally absorbed into the job. What we will not do is start work of unknown cost without telling you first.

New equipment carries the manufacturer's warranty, and we administer the claim for you. Warranty generally does not cover normal wear, consumables, running a machine dry, incorrect pressure or temperature settings, off-ratio or contaminated material, freezing, missed maintenance or unapproved parts. We will tell you honestly what the manufacturer decides. See our Refund & Returns Policy.

Start with the basics before you call: A and B pressures at the gauges, hose temperature at both sides, whether both transfer pumps are keeping up, filter screens, and whether either drum is low or crusted. Note the actual numbers you see — that single detail lets us narrow the cause on the phone in minutes rather than guessing.

Yes. We service the platforms listed above regardless of where you bought them.

Often, yes. Tell us the location and the fault when you book and we will tell you whether a site visit or a bench repair gets you spraying sooner.

Yes, and it is far cheaper than an emergency. An annual or seasonal service — seals, filters, screens, lubrication, calibration check — prevents most of the failures we see in the middle of a job. Choose "Preventive maintenance" in the form below.

Maintenance depends on the equipment, its operating hours, and the conditions it works in. An hour-based service schedule is useful for equipment such as compressors, but it doesn't replace daily checks or calendar-based maintenance. Keep a record of the hours, service dates, and work performed so you know what's actually due.

For your Reactor, follow the maintenance schedule for the exact model, including checks of the specified pump lubricant or TSL system. Check fluid level and condition as directed, and don't wait for a calendar date if the fluid needs attention sooner. Pump seals and rebuilds also need to be assessed using the model's inspection and repair guidance. A leak or performance problem should be checked when it appears.

Use Graco's Reactor maintenance guide for the detailed schedule and related service instructions. If you send us your compressor and Reactor model numbers, we can help you identify the correct maintenance information for your rig.

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