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Kohler Tresham Comfort Height One-Piece Compact Elongated Toilet

Model number
K-3981-0

The Kohler Tresham K-3981-0 is a premium one-piece compact elongated toilet with a skirted trapway that gives it a cleaner, more furniture-like profile. It combines a 1.28 GPF AquaPiston flush with Comfort Height seating and an included slow-close seat, making it well suited to bathrooms where appearance and daily comfort are both priorities. The skirted base also reduces the hard-to-clean contours found on exposed trapway toilets.

identifiers stable · addressable
Model no.
K-3981-0
Brand
Kohler
Category
Toilet
Canonical URL
/kohler/toilet/k-3981-0-kohler-tresham-comfort-height-one-piece-skirted-toilet/
Official page kohler.com →
14 spec rows · each row is anchorable

§ Specifications

#specifications
Product Type
one-piece
Bowl Shape
compact elongated
Gpf
1.28
Flush Technology
AquaPiston
Height Type
comfort-height
Seat Height In
17.5
Trip Lever
left-hand
Trapway
concealed
Rough In In
12
Seat Included
Yes
Seat Type
slow-close
Color Finish
White
Water Sense Certified
Yes
Warranty
Limited Lifetime

§ What's Included

01 One-piece toilet
02 Slow-close seat
03 Left-hand trip lever
04 Mounting hardware

§ Warranty

Limited Lifetime

§ FAQ

What rough-in does the Tresham K-3981-0 use?

This one-piece Tresham model is intended for a 12-inch rough-in. You should measure from the finished wall to the center of the floor flange bolts before purchase, since skirted one-piece toilets generally offer less installation forgiveness than standard exposed-base bowls. Matching the rough-in correctly is the easiest way to avoid fit and clearance problems.

How does the flush performance compare to a conventional toilet?

The AquaPiston system is designed to deliver a strong gravity flush using 1.28 gallons of water, helping balance efficiency and solid waste removal. Because the canister valve opens more fully than a traditional flapper, water can enter the bowl quickly and with less restriction. That setup is aimed at providing reliable flushing performance without resorting to louder pressure-assist hardware.

Can this toilet accept an aftermarket seat even though it includes one?

Yes, you can replace the included slow-close seat if you prefer a different feel, material, or feature set. Since this is a compact elongated bowl, seat fit needs more attention than on a fully standard elongated profile, so compatibility should be verified before buying an aftermarket option. Kohler-branded seats usually offer the safest cosmetic and dimensional match.

Why choose Comfort Height on a one-piece model like this?

Comfort Height brings the seat position up to a more chair-like level, which many adults find easier for everyday use. On a premium one-piece toilet, that ergonomic benefit is often part of the overall upgrade rationale along with easier cleaning and a more refined design. It can be especially useful in primary baths or remodels intended to remain comfortable for years.

Is the Tresham K-3981-0 water efficient and WaterSense certified?

Yes. This toilet uses 1.28 gallons per flush, lowering water consumption compared with legacy 1.6 GPF and older high-volume toilets. Per your rule set, all 1.28 GPF models here are marked WaterSense certified, so this model is treated as meeting that efficiency expectation while remaining in a premium one-piece format.