Why the hiring decision matters more here
A sealant joint in Fargo works harder than the same joint in Kansas City. Panel and masonry joints move with temperature, and the Red River Valley delivers one of the widest annual swings in the lower 48. The National Weather Service office serving Fargo has recorded winter lows past 30 below and summer highs over 100, and a dark panel face in July runs far hotter than the air. A joint installed with sloppy prep might survive five years in a mild climate. Here it opens up by the second winter, and by then the installer is long gone.
That is why the contractor matters more than the tube. The best polyurethane on the market fails early over dirty concrete or without backer rod, and a mid grade sealant installed correctly will outlast it. You are really buying prep discipline, and prep is invisible in a finished bead. The checks below make it visible before you sign.
What should I look for before hiring a caulking contractor?
Look for full cutout of the old sealant, a named sealant that meets ASTM C920 Class 25 or better, correct backer rod sizing, and a stated temperature window for installation. Any bid missing one of these is a bid for a short lived joint. Here is what each one means in practice:
- Full cutout, both joint faces. New sealant bonded to old, failed sealant fails with it. The scope line should say cut out and remove existing sealant, not recaulk or reseal over.
- A named sealant with a movement class. Commercial joint sealants are specified under ASTM C920, which classes sealants by how much joint movement they tolerate. For precast panel and expansion joints in this climate you want Class 25 minimum, and Class 50 on wide or high movement joints. A bid that just says caulk is not a spec.
- Backer rod in the scope. Closed cell backer rod sets the sealant depth and creates the hourglass profile that stretches instead of tearing. If backer rod is not a line item, the installer is probably filling the joint solid, which is the most common cause of early cohesive failure.
- A temperature and moisture window. Most polyurethanes want the substrate at 40 degrees and rising, dry, and frost free. A contractor who will gun sealant in late November in Fargo without a low temperature product or hoarding plan is telling you how they work.
- Certificates of insurance before mobilization. General liability and workers comp, sent from their agent to you, with your entity listed. Swing stage or lift work on a parking structure without workers comp is your risk, not theirs.
What questions should I ask before signing?
Ask seven questions and require specific answers: what gets cut out, which sealant and class, how joints are cleaned, how the price was measured, what the warranty covers, who is actually on the wall, and what happens when weather closes the window. The table shows what a good answer sounds like next to a weak one.
| Question | Good answer | Weak answer |
|---|---|---|
| What happens to the old sealant? | Cut out completely, joint faces cleaned or ground | We seal over it where it is still solid |
| Which sealant will you use? | Named product, ASTM C920 Class 25 or 50 | Commercial grade caulk |
| How did you measure the price? | Per linear foot, quantities shown by elevation | Lump sum, no quantities |
| What does the warranty cover? | Adhesion and workmanship, 5 years or more, in writing | We stand behind our work |
| Who does the installation? | Own crew, foreman named | We use good subs |
| What if it gets too cold mid job? | We stop, or switch to a low temperature rated product | We work year round, no problem |
| Can I see a similar local job? | Addresses of precast or garage work you can drive past | Photos only, no locations |
How pricing tells you who to trust
A contractor confident in their production rates will price per linear foot, and the number should land in a knowable range. In the Fargo market, ground level precast panel joint resealing runs about $4 to $8 per linear foot, elevated work more, and parking garage expansion joint systems are their own category. Our published cost guide breaks those ranges down by job type. When a lump sum bid comes in far under the per foot math, the missing money is almost always prep: no cutout, no backer rod, or a crew racing the daylight.
Be careful comparing a full joint sealant replacement bid against a patch and spot repair bid. They are different scopes, and a low number for the second is not a deal on the first. Ask every bidder to price the same measured quantities so the numbers actually compare.
Local proof beats a national logo
A contractor who has resealed tilt-up and precast buildings along the I-29 and I-94 corridors knows what our freeze and thaw cycling does to a joint shoulder, and which products stay workable when the crew is chasing 45 degree afternoons in October. Ask for two or three addresses of work that has been through at least two winters, then drive past. A joint that still looks tooled and tight after two Fargo winters is the only reference that matters.