Cracked panels and worn fireplace parts fixed in Lake Sunset

The hearth extension in front of a prefab unit

Section R1004.2 says the hearth extension of a factory-built fireplace follows the listing of the fireplace, stays readily distinguishable from the surrounding floor and, when it is a listed product, complies with UL 1618.

In one maker's manual, that extension reaches 20 inches in front and 12 inches beyond each side, over a layer with a stated insulating value. We measure yours against your own model's figures when the hearth is part of the repair.

Grate retainers and firebox floors

Some factory-built fireplaces use grate retainers fastened near the back of the firebox floor to hold the grate in its intended position. One maker's instructions fix them with masonry screws and specify its own grate only.

A grate that slides forward sends burning logs toward the opening and the screen. We refit missing retainers and replace worn grates with the listed part for your model.

• Retainers fixed near the back of the floor
• The maker's grate for the model
• Grate held in its intended position

What zero clearance really means

Zero clearance describes a fireplace built to sit close to wood framing, with air spaces and shields built into it. It does not mean any material can touch any part of it. Each model lists its own clearances, and those figures are part of its listing.

We read the clearances in your model's manual before any repair near the framing or the face, and we point out finishes that have crept closer than allowed.

The first fire after a prefab repair

New parts can come with break-in instructions from their maker, and we follow whatever comes with yours. Before we leave, we open and close the damper, check the doors or screen and walk you through lighting the first fire.

Keep that first fire modest and watch how it draws. Anything that seems different from before is worth mentioning to us, so we can talk it through while the repair is fresh.

• Damper opened and closed
• Doors or screen checked
• Break-in instructions followed
• A modest first fire