A tankless water heater heats water on demand as it flows through the unit, rather than storing 40-75 gallons at temperature around the clock. That means no run-out during back-to-back showers, a smaller footprint on the wall, and lower standby energy loss than a tank.
Converting from a tank to tankless in an older Sherrelwood home almost always involves two things a straightforward tank swap doesn't: verifying (and often upsizing) the gas line to handle the tankless unit's higher burner output, and adding dedicated venting, since tankless units use different combustion venting than most existing tank setups.
We evaluate both of these during your quote so the number you're given up front is the number you actually pay — not a lowball that grows once we're on-site.
Good candidates for tankless
- Households that regularly run multiple showers or a shower and laundry at once
- Homeowners wanting to free up floor space in a small mechanical closet
- Anyone replacing a unit that's about to fail and open to upgrading rather than like-for-like
- Homes with an existing 3/4-inch gas line, or budget to upsize it
OUR TANKLESS INSTALLATION PROCESS
What happens during this service
Gas & venting evaluation
We check your existing gas line diameter and venting path against the new unit's requirements before quoting a final price.
Unit sizing
Tankless units are sized by flow rate (GPM), not gallons — we size yours to your home's simultaneous hot water demand.
Removal & mounting
The old tank is drained and removed; the new tankless unit is wall-mounted, typically taking up a fraction of the old footprint.
Gas line & venting work
Gas line upsizing and new dedicated venting are completed and permitted as needed.
Commissioning
We run the unit through hot water draws at multiple fixtures to confirm consistent temperature and flow before we leave.
PRICING
What affects tankless installation cost
We quote a flat rate on-site before starting any work. These are the main factors that move price up or down for this service in Sherrelwood:
- Whether your existing gas line needs to be upsized for the new unit
- Whether new venting needs to be run, and the length/complexity of that run
- Unit capacity (GPM rating) required for your household's peak demand
- Electrical outlet availability for the unit's igniter and controls
FAQ
Common questions about this service
Will a tankless unit really give me endless hot water?
Within the unit's rated flow capacity, yes — it heats water as it flows rather than depleting a stored supply. Running more fixtures simultaneously than the unit is rated for will reduce flow, which is why sizing correctly matters.
Is my gas line big enough for a tankless unit?
Often it needs to be upsized from the 1/2-inch line common with older tank setups to 3/4-inch. We check this during your quote rather than assuming.
How much more efficient is tankless than a tank?
Tankless units avoid the standby heat loss of a tank sitting at temperature all day, typically running 8-14% more energy efficient for an average household, with bigger savings for lower-usage households.
Can you install tankless in a small mechanical closet?
Usually yes — the compact wall-mounted footprint is one of the main advantages over a tank, though venting clearance still needs to be verified.
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