[Intro]
[Acoustic guitar - dry, picked in 3/4 time]

[Verse 1]
I put the in-floor heating in
Her sister's rec room back in oh-eight
Six inches reinforced with mesh
PEX tubing sealed in the pour
I told them it would take three days
Before the thermal mass would rise
But I never said how long it holds
The warmth after the thermostat dies

[Chorus]
My heart is six inches of poured concrete
With plastic piping running through the middle
Takes seventy-two hours just to warm the slab
And a week to cool when she stops calling
You can bring propane torches to the job site
But you cannot force the cure with open flame
Some foundations are designed to store
Way more heat than they ever release

[Verse 2]
There's salt rings on her hardwood floor
From my Baffin boots in December
Tracked the calcium across the grain
When I came to check the manifold
The pressure gauge read sixty PSI
But the circulation pump was gone
Now I calculate the heat loss rate
In calories of what went wrong

[Chorus]
My heart is six inches of poured concrete
With plastic piping running through the middle
Takes seventy-two hours just to warm the slab
And a week to cool when she stops calling
You can bring propane torches to the job site
But you cannot force the cure with open flame
Some foundations are designed to store
Way more heat than they ever release

[Bridge]
Engineers call it thermal flywheel
The capacity to hold and wait
A concrete slab don't care if you freeze
It releases on its own damn date

[Guitar Solo - pedal steel swells]

[Outro]
Three days to warm up
One week to let go
The PEX is still carrying
What the thermometer don't show