Plumbing codes ask for the joint where a toilet meets the floor to be sealed or watertight, though South Carolina’s version of the IRC exempts toilets. GE names a bathroom silicone for the job.
Where
Painting over it?
What to use
100% silicone made for kitchen and bath
No caulk data sheet we read lists a toilet base. GE’s toilet guide calls for a silicone sealant made for bathroom use.
DAP 100% Silicone Kitchen, Bath & Plumbing (100% silicone): water ready in 12 hours, not paintable.
GE Advanced Silicone 2 Kitchen & Bath (100% silicone): water ready in 30 minutes under GE’s conditions, otherwise 8 hours, not paintable, rated for ±35% movement.
3 more products list it.
Plumbing codes ask for the joint to be sealed. The IPC (section 405.6) says joints where fixtures meet walls or floors shall be sealed, and the IRC (P2705.1) says the contact area shall be watertight. States change these: South Carolina’s IRC says toilets don’t have to be caulked to the floor, so check your local code.
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What the codes say
Fixture-to-floor joints, in each code’s words
Code
Text
International Plumbing Code, 405.6
Joints formed where fixtures come in contact with walls or floors shall be sealed.
International Residential Code, P2705.1
Where fixtures come in contact with walls and floors, the contact area shall be watertight.
South Carolina’s IRC
Exception: Water closets and/or bidets shall not be required to be caulked to flooring surface.
California Plumbing Code 2025, 402.2 (based on the UPC)
Where a fixture comes in contact with the wall or floor, the joint between the fixture and the wall or floor shall be made watertight.
IPC and IRC text as adopted in South Carolina and Virginia, read on UpCodes; the California text from a third-party copy on gocodebook.com. None names a caulk type, and your local code decides.
How GE says to do it
Use a silicone sealant made for bathrooms; GE names its Advanced Silicone Kitchen & Bath.
Run one continuous bead along the floor-to-base joint, around the front and sides. Don’t caulk between the tank and bowl.
Take the old caulk out first: GE says new over old prevents proper adhesion.
Don’t use the toilet too soon. Oatey says curing usually takes around 24 hours.
The gap at the back
GE’s guide notes that some professionals leave a small gap at the back, so a hidden leak shows instead of being trapped. Oatey says water is more likely to run down the flange pipe than out the back, and recommends caulking the entire base. Check your local code first.
Not plumber’s putty: Oatey, which makes it, says putty isn’t designed for a toilet base and that cleaners and urine may compromise it.
The code lines come from the IPC and IRC as adopted in South Carolina and Virginia (read on UpCodes) and the California Plumbing Code (a third-party copy), and the method from GE’s and Oatey’s own guides. Checked against published data from GE Sealants, DAP, International Code Council, Oatey and Red Devil (plus 2 more).
See all 18 sources
DAP, 100% Silicone Rubber Kitchen, Bath & Plumbing Sealant: product page, FAQ and technical data sheet
DAP, KWIK SEAL Kitchen & Bath Adhesive Caulk: product page, FAQ, technical data sheets (white and clear) and SDS
DAP, AMP Advanced Kitchen & Bath Sealant: product page, FAQ, technical data sheet (2022) and SDS
DAP, SILICONE MAX Premium Kitchen & Bath 100% Silicone Sealant: product page, FAQ, technical data sheet and SDS
GE Sealants, Advanced Silicone 2 Kitchen & Bath Sealant: product page, technical data sheet (2025) and SDS
GE Sealants, Supreme Silicone Kitchen & Bath Sealant: product page, technical data sheet (2025) and SDS
GE Sealants, Paintable Silicone Supreme Kitchen & Bath Sealant: product page, technical data sheet and SDS
GE Sealants, Pro Seal Max Kitchen & Bath Sealant: product page, technical data sheet and SDS
GE Sealants, Advanced Siliconized Acrylic Kitchen & Bath Sealant: product page, technical data sheet (2024) and SDS
GE Sealants, Tub & Tile Silicone 1 Kitchen and Bath: product page, technical data sheet (2026) and SDS
GE Sealants, “How to Recaulk a Toilet” (how-to, 2026)
Red Devil, Kitchen & Bath Siliconized Acrylic Sealant: product page, technical data sheet, FAQ and SDS
Sashco, Lexel: product page, technical data sheet and SDS (2024)
International Plumbing Code 2021 and 2024, section 405.6 Watertight Joints (as adopted in South Carolina, read on UpCodes)
International Residential Code 2021, section P2705.1 (as adopted in Virginia and in South Carolina, read on UpCodes)
Oatey, “Plumber’s Putty: What It Is, How to Use It and When Not to Use It” (blog, 2026)
Oatey, “Should You Caulk Around a Toilet?” (blog, 2024)
2025 California Plumbing Code (Title 24, Part 5, based on the Uniform Plumbing Code), section 402.2 Joints (as reproduced on gocodebook.com)
General guidance from manufacturer and standards data. Products vary, so check the label and the maker's instructions.