Damaged chimney flues fitted with new liners in Tangelo Park

Proving the flue before the liner is ordered

It pays to prove the inside of a chimney before installing a liner. One manufacturer suggests lowering a short piece of liner of the intended size down the chimney, or using a liner guide cone, to see whether it passes all the way to the bottom.

We do that before parts are ordered, so a hidden restriction shows up on inspection day rather than installation day. If the test piece stops, we find where and why, whether it is an offset, a broken tile or old debris, and the estimate reflects what it will take to get past it.

No change in flue shape at the roof line

Section R1003.6 says the chimney wall or flue lining shall not change size or shape within 6 inches above or below where the chimney passes through floor, ceiling or roof components.

When a relining plan involves a transition, an adapter or an oval section, we keep it clear of those zones and show where it falls on the route. That is one more reason the route is mapped before ordering, since the location of a transition is fixed by the chimney, not chosen on the day.

Changing fuel means rechecking the liner

Moving from one fuel to another is one of the changes that calls for a fresh look at the flue. The lining must suit the appliance connected, and the new appliance's instructions may call for a different size or product.

We review the liner against the new appliance before it is connected, not after the first problem. If the existing liner can stay, we tell you and explain why it still qualifies.

How the installation day runs

Relining day follows a set order, and we tell you the plan the day before, including when the fireplace and the roof will be in use and roughly how long each stage takes for your chimney.

• The flue and smoke chamber are cleaned
• The route is proven with a test piece or guide cone
• Insulation, where required, goes on the liner
• The liner is lowered from the top
• The base connection is made and checked
• The top plate and liner cap are fitted and fastened