Fireplace Insert or Open Hearth: What Changes for Orland Park Homeowners
By Dan Joel, Elite Sweepers Inc.
An open masonry fireplace is a lovely thing and a poor heater. That is not a criticism, it is just what it is: a large opening drawing heated room air up the flue, giving back radiant warmth to whatever is directly in front of it. Once a household starts thinking about actually heating with the fireplace, the conversation turns to inserts, and the differences go beyond efficiency.
What an open hearth actually does
The short answer: it radiates heat forward while sending a large volume of household air up the chimney.
The fire needs air, and it takes that air from the room. The room’s air has already been heated by your furnace. So while you feel warmth from the fire in front of you, the house as a whole is losing conditioned air continuously through the flue. On a cold night with a modest fire, it is entirely possible for the rest of the house to get cooler while the fireplace room feels warm.
What an insert changes
The short answer: it encloses the fire, controls its air, and moves heat into the room instead of up the chimney.
An insert is a firebox that sits into the existing masonry opening, with a sealed glass front and controlled air intake. Because the fire is enclosed, it is no longer consuming room air freely, and because combustion can be regulated, the fire burns more completely and for longer on the same wood. Heat transfers into the room through the unit’s surfaces, often with a fan, rather than escaping past the fire.
What you give up is the open fire itself. There is glass between you and the flames, and there is no cooking over it or listening to it the same way. That is a real trade and worth being honest about, because some households value the open hearth more than the efficiency.
The part people miss: the liner
The short answer: an insert needs a properly sized liner running the full height, not the original oversized flue.
This is where installations go wrong. The original masonry flue was sized for an open fireplace, meaning a large volume of hot gas. An insert produces a much smaller volume of cooler exhaust. Vent that into the original oversized flue and the gases cool as they rise, slow down, and condense on the walls, which produces heavy creosote and poor draft. A correctly sized stainless liner running from the insert to the top of the chimney is what makes the system work as intended. Our chimney relining page covers what that involves.
What maintenance looks like afterward
The short answer: still annual, and in some ways more particular.
Inserts still need sweeping, and the liner, the connection at the insert, the gasket around the glass and the baffle inside all need checking. Because an insert can run long slow burns, and long slow burns are exactly what deposits creosote, an insert operated on a low setting with mediocre wood can build up faster than an open fireplace would. Dry wood matters even more here, not less. Our chimney sweeping page covers the visit.
Which to choose
The short answer: if you want ambience a few evenings a year, keep the open hearth and maintain it. If you want the fireplace to contribute real heat, an insert is the answer, budgeted with the liner included rather than as an afterthought.
For local scheduling, see our chimney service in Orland Park, the full list of services, and our pricing page for costs. Elite Sweepers Inc is insured and bonded, works seven days a week from 7 AM to 7 PM, and gives you the price before starting. Call (708) 432-3977.
Insert and Open Fireplace Questions
Is an open fireplace really inefficient?
As a heat source, yes. It radiates warmth forward but simultaneously draws heated room air up the flue to feed the fire, so the house as a whole often loses more heat than the fireplace contributes.
Does a fireplace insert need a chimney liner?
Yes, and it is not optional. An insert produces a smaller volume of cooler exhaust than the original flue was sized for, so without a correctly sized liner the gases cool and condense, producing heavy creosote and poor draft.
Can an insert be installed in any fireplace?
Most masonry fireplaces can accept one, but the opening dimensions, the condition of the existing structure and the chimney height all need checking first. That assessment should happen before a unit is chosen.
Do inserts still need annual sweeping?
Yes. The liner, the connection at the unit, the glass gasket and the internal baffle all need attention. Inserts run on long slow burns can actually accumulate creosote faster than an open fireplace.
Will I lose the look of an open fire?
To a degree. An insert has a sealed glass front, so you see the fire but do not have an open hearth. Households that value the open fire above heating output are often better keeping what they have and maintaining it well.
Does an insert help with drafts from the fireplace?
Generally yes. Because the unit is sealed and its air intake is controlled, it stops the fireplace acting as a large open path between the house and the outside when not in use.
What kind of wood should I burn in an insert?
Well-seasoned hardwood, and it matters more than with an open fireplace. Inserts are often run at lower burn rates, and low burn rates with wet wood are the fastest way to build up creosote in the liner.
How long does an insert installation take?
It depends mainly on the liner. A straightforward chimney can often be done in a day, while one with offsets, multiple flues or masonry needing repair first will take longer. We confirm the scope before starting.
Published September 21, 2026