Subfloor Moisture Results to Go or No-Go

Takes your moisture test readings and the flooring maker's stated limits, compares them one by one, and gives a clear go or no-go recommendation for installation.

FlooringHome Services and Trades✓ Checkedv1.0

Before and after

BEFORE · what the owner typed

Ari Quinn here from Fairhill Flooring. Need a go/no-go for Beatrice Sears, 745 Deerhill St, Lindendale. Kitchen and hall, about 420 sq ft, concrete slab on grade. Installing Quillon Grove 7 inch wide plank engineered hickory, floating. She wants to start Monday. I did RH probes in 3 spots: kitchen by the sink wall 71%, middle of the hall 74%, and by the back exterior door 82%. Also did one calcium chloride test by the back door, 4.1 lbs per 1000 sq ft per 24 hrs. The Quillon Grove sheet I have says max 75% RH and max 3.0 lbs on calcium chloride for floating over slab. Room was 68 degrees and 45% humidity. There's a darker stain on the slab near the back door. Her number is 262-555-0198.

AFTER · what the skill produced

DECISION: NO-GO for Beatrice Sears, 745 Deerhill St, Lindendale

Readings (limits are from the Quillon Grove sheet you gave me)

RH probe, kitchen by sink wall: 71%. Limit 75%. Pass, 4 points under.
RH probe, middle of hall: 74%. Limit 75%. Pass, 1 point under.
RH probe, by back exterior door: 82%. Limit 75%. Fail, 7 points over.
Calcium chloride, by back exterior door: 4.1 lbs per 1000 sq ft per 24 hrs. Limit 3.0. Fail, 1.1 over.

Of 4 readings, 2 pass and 2 fail.

What this means
Two readings at the back door are over the limit you gave me, and they agree with each other. You also noted a darker stain on the slab in that spot. Because this is one floating floor across 420 sq ft, we recommend not installing until the back door area is corrected and the slab is retested. The hall reading passes by only 1 point, so we recommend watching it closely on the retest.

Next steps we recommend

Find out why the area by the back exterior door is wetter than the rest of the slab.
If the cause is something a licensed plumber, contractor, or other professional needs to look at, have them assess it.
Ask Quillon Grove in writing whether a moisture barrier or mitigation system is approved for this product, and what they require.
Retest the slab, including the hall, and run this comparison again.

Message for the customer
Hi Beatrice, this is Ari from Fairhill Flooring. Before we start your kitchen and hall floor, we tested the concrete slab for moisture. The areas near the kitchen sink and in the middle of the hall were within the flooring maker's limits. The area by the back door was over the limit on both tests we ran, and we noticed a darker stain there too. We recommend not starting Monday. We want to correct the moisture first, then retest, so your new floor is installed on a slab that meets the maker's requirements. We will walk you through the options. You can reach me at 262-555-0198.

Questions for the owner

Please confirm the 75% RH and 3.0 lbs limits against the current Quillon Grove written instructions for floating installs.
Do you want to quote a mitigation option, and if so, what product and price should go in the message?
Is there a new target start date to offer Beatrice, or should we say we will confirm after retesting?
Do you know anything about the slab's history or how the area outside the back door drains?
Do you want to recommend a specific professional for the stain, or leave that to the customer?

What it does

Takes your moisture test readings and the flooring maker's stated limits, compares them one by one, and gives a clear go or no-go recommendation for installation. It also writes a short plain-English note for the customer.

Use it when: Use when a flooring business has subfloor or slab moisture test results and needs a clear go or no-go recommendation for installation, such as: "are these moisture readings okay," "can we install Monday," "write up the moisture test," or "tell the customer about the slab test."