Exit 14 / How-To Library
Understand the pipes
before the estimate.
14 illustrated explainers on how home plumbing works, what inspectors look for and which questions to ask. Learning material, not a substitute for a licensed on-site assessment.
Updated 2026-10-14
Showing 14 of 14 guides
Not to scale Educational illustration only; not an installation plan or real job photo. Sewer & drainage5 minHow a Main Sewer Line Is Installed: Slope, Connections & Cleanouts
Understand sewer slope calculations, drainage fittings, bedding and the checks to discuss with your inspector before a main sewer line is buried.
Read guideNot to scale Educational illustration only; not an installation plan or real job photo. Sewer & drainage4 minUnder-Slab Sewer Plumbing: What to Check Before Concrete
Plan underground drain piping under a slab: fixture layout, slope, footing penetrations, bedding, testing and inspection before the pour.
Read guideNot to scale Educational illustration only; not an installation plan or real job photo. Sewer & drainage4 minSewer Plumbing Under a Raised Foundation
Learn how crawlspace drains differ from buried sewer piping, including hangers, slope, cleanouts, ground clearance and safe access.
Read guideNot to scale Educational illustration only; not an installation plan or real job photo. Sewer & drainage4 minVertical Sewer Stacks & Vents: How the System Works
Understand drain stacks, vent pipes, trap seals, fitting direction, roof terminations and the common venting mistakes that lead to sewer odors.
Read guideNot to scale Educational illustration only; not an installation plan or real job photo. Water supply4 minMain Water Line Installation: Sizing, Shutoffs & Pressure
Understand the water service from meter to house, including pipe sizing, approved materials, shutoffs, pressure regulators and inspection.
Read guideNot to scale Educational illustration only; not an installation plan or real job photo. Water supply4 minVertical Water Lines: Risers, Supports & Wall Protection
Learn how vertical hot and cold water lines are planned, supported and protected, including expansion, nail plates and firestopping.
Read guideNot to scale Educational illustration only; not an installation plan or real job photo. Water supply4 minRunning Water Lines in a Crawlspace vs. an Attic
Compare water-pipe routes through attics and crawlspaces: heat, access, leak consequences, insulation, supports and repair planning.
Read guideNot to scale Educational illustration only; not an installation plan or real job photo. Water supply4 minPEX Plumbing: Benefits, Connections & Installation Mistakes
Explore PEX benefits and limits, compatible fittings, bend protection, supports and why pressure testing must follow the exact manufacturer's instructions.
Read guideNot to scale Educational illustration only; not an installation plan or real job photo. Gas safety4 minMain Gas Lines: Planning, Sizing & Inspection
Understand a professional gas-line proposal: appliance loads, meter capacity, pipe sizing, material approvals and inspection before service.
Read guideNot to scale Educational illustration only; not an installation plan or real job photo. Gas safety4 minGas Lines in Crawlspaces: What a Safe Installation Needs
Learn what to ask a qualified installer about crawlspace gas piping, including corrosion, supports, damage protection and inspection access.
Read guideNot to scale Educational illustration only; not an installation plan or real job photo. Gas safety4 minGas Lines in Attics: Routing, Protection & Inspection
Review the questions to ask before professional attic gas work: approved materials, supports, heat exposure, access and commissioning.
Read guideNot to scale Educational illustration only; not an installation plan or real job photo. Fixtures & finishes4 minInstalling Plumbing Finishes: Toilets, Faucets & Shower Trim
Check finished plumbing for compatible trim, toilet flange support, shutoff access, trap connections, temperature control and leaks.
Read guideNot to scale Educational illustration only; not an installation plan or real job photo. Fixtures & finishes4 minHose Bibs: Mounting, Backflow Protection & Leak Checks
Learn what a properly installed outdoor faucet needs, including secure mounting, approved backflow protection, pressure checks and freeze planning.
Read guideNot to scale Educational illustration only; not an installation plan or real job photo. Testing & inspection5 minPlumbing Pressure Tests: Water, Drains & Gas Are Different
Compare service water pressure, DWV water-head tests and professional gas tests. Learn why pressure, medium, duration and local approval all matter.
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