How To Seal Rim Joists

Low Pressure Foam

Unsealed rim joists rob homeowners of money, energy efficiency and comfort. Fill gaps and penetrations greater than 2” quickly and affordably with the Froth-Pak™ Spray Foam Sealant Kit.

Materials

Eye Protection
Waste Receptacle
Cloth
Tyvek® hooded coveralls
Nitrile gloves
Respirator with P100 organic vapor cartridge
A Froth-Pak™ Spray Foam Sealant Kit

Step by Step Instructions

Make sure all flame sources are extinguished.
Prep area by removing all water, oil, dust, dirt or debris.
Read the included manual to ensure you meet all OSHA requirements.
Check if the kit contents are between 70°F-120°F.
Gently rock tanks back and forth.
Lift the Insta-Flow Dispenser from the box and attach the hoses to the tank with the wrench provided.
Coat the inside face of the Insta-Flow Dispenser with petroleum jelly (included).
Fully open both tank valves.
Check for products flowing through the lines. If not, shut the valves and check the troubleshooting guide in the manual.
Pull the trigger to purge the lines into an appropriate waste receptacle until both streams are equal.
Wipe down the dispenser and apply more petroleum jelly.
Push the nozzle (included) firmly into the Insta-Flow Dispenser, listen for a snap.
Hold the Insta-Flow Dispenser at least 6 inches from the spray area and pull the trigger when ready.
Move-in a steady stroke around the joist.
Keep in mind that foam cures in just 30-60 seconds.
Push down on the ejector to remove the nozzle once spraying is complete.
Clean product from the dispenser with a cloth and apply petroleum jelly one last time.
Firmly reinsert nozzle for an airtight seal.
19. Close both cylinder valves and store for up to 30 days.
20. Continue ventilating the area for at least another hour. Do not enter during ventilation without a respirator and other safety gear.

Helpful Tips

Froth-Pak™ Spray Foam Sealant comes in a variety of sizes to suit your needs.
The self-contained portable kits contain everything you need, with no additional gas cylinder or electricity required.
Avoid exposing cured foam to temperatures above 240°F.
Tubing inside the tank can become damaged if shaken too hard.
If applied outdoors, be sure to paint or cover foam to prevent discoloration and UV damage.
Always refer to the installation guide for safe usage and local building codes prior to application.
For best results, the tank contents should be at 75°F (24°C) or warmer. Ambient and surface temperatures should be 65°F or above.
The temperature indicator – not available on Froth-Pak™ 650 kits – on the side of the tank shows the temperature of the contents of the tank, not the ambient air temperature.
Froth-Pak™ Foam can be applied effectively in cooler air temperatures or on cooler work surfaces provided the kit contents are at least 75°F (24°C). (See user manual, Section 4.3 - Cold weather spray guidance)
If hoses are not already attached, use the wrench provided in the Gun / Hose Assembly Kit or your own 5/8” wrench to tighten the hose assemblies for both “A” and “B” valves until both are tight.
Apply petroleum jelly to the inside surfaces of the face of the gun
Do not attempt to reuse the nozzle if the spray has stopped for more than 30 seconds (or more than 15 seconds for the FROTH-PAK™ High-Density product). Restart times are impacted by temperature. (See section 3.2 in user manual)
Do not reuse a cured or partially cured nozzle. This may cause foam to crossover in the gun, rendering it unusable.
If A:B ratio appears wrong, check face of the gun to ensure the ports are clear of cured material (you should be able to see the silver finish of the aluminum spool in the ports). Purge foam through gun for a few seconds without a nozzle. Replace nozzle and try again.
To prevent foam from running or dripping from substrate, spray thinner passes. · The foam expands more than the previous formulation, so spray faster passes. Initial spray does not need to be as thick to result in the same desired final thickness.
Apply a flash-coat for optimal adhesion in suboptimal conditions (cool weather, difficult substrates). A fan nozzle is best used for this. Spray a very thin layer (~1/4” thick) on entire surface to be foamed. Allow the foam to become tack free (~1 minute). Then spray as usual to desired thickness.