What to know before you start
A new furnace or air conditioner is often sold by the box: brand, size, efficiency rating. The work around the box matters just as much. Duct changes, venting, the gas line, the condensate drain, the thermostat and the permit can all be in one bid and missing from another.
DougCO Builds writes all of it into one scope. Our estimator records your current equipment, the rooms that run hot or cold, the duct layout and the space around the unit. Contractors bid on that, and you compare the same job from every bidder.
What the job includes
- Furnace, air conditioner or heat pump replacement
- A load calculation so the new system is sized to the house, not just matched to the old one
- Venting, combustion air and gas line connections
- Condensate drain, and a pump where one is needed
- Duct repairs, sealing, new runs and return air changes
- Thermostat install and setup
- Whole-home humidifier and air filtration add-ons
- Removal of old equipment, including refrigerant recovery
What we scope
Furnace replacement
Standard and high-efficiency gas furnaces, set up for our altitude and vented to current code.
Air conditioning
Central AC added to an existing furnace system, or replaced alongside it.
Heat pumps
Ducted heat pumps, including cold-climate models and dual-fuel setups that keep a gas furnace as backup.
Ductless mini-splits
Heating and cooling for a bonus room, basement, garage or addition the main system doesn't reach well.
Ductwork and air quality
Duct repairs, new runs, balancing, humidifiers and filtration.
What drives the cost
Every project is different, so your True Bid prices yours line by line after the site visit. These are the things that move the price most.
- Equipment type and efficiency
- Higher-efficiency furnaces, variable-speed blowers and heat pumps cost more up front than basic single-stage units.
- System size
- Size should come from a load calculation. An oversized unit costs more and cycles on and off too often.
- Venting changes
- Moving from an older furnace to a high-efficiency one usually means new plastic venting through a wall or roof.
- Ductwork condition
- Leaky, undersized or poorly balanced ducts may need work before new equipment can do its job.
- Access
- A unit in a tight crawlspace or attic takes more labor than one in an open basement.
- Electrical and gas updates
- A heat pump or new AC may need a new circuit, and a new furnace may need gas line changes.
Permits and HOAs in Douglas County
Most furnace, air conditioner and heat pump replacements need a mechanical permit and inspection, and gas line work almost always does. The inspector checks venting, gas connections, combustion air and electrical hookups, the parts of an install you can't see once it's running.
Castle Rock, Parker, Lone Tree, Castle Pines and Larkspur issue their own permits. Highlands Ranch and the rest of unincorporated Douglas County use the county's Building Division. Ask any contractor whether they are licensed or registered with the department that covers your address.
Built for Douglas County
Altitude matters for gas equipment. Furnaces lose capacity in thinner air, so manufacturers often derate them or offer models specified for high elevation. A good bid accounts for that instead of copying the old unit's label.
Our climate is dry, with cold winters, sunny summers and big swings in between. Many homeowners add a whole-home humidifier, and some older homes still cool with evaporative coolers. Wildfire smoke days have also made better filtration a more common request.
How DougCO Builds runs your project
- Tell us about itSend the basics through the project form. We call to set up a site visit.
- One site visitOur estimator measures, photographs what's there and talks through what you want.
- Your True BidYou get a written, line-by-line scope and a budget before any contractor sees the job.
- Contractors bid on the same scopeVetted local contractors bid without your contact details. You compare the bids side by side.
- We manage it with youWe check insurance and licensing before work starts, then walk the job at milestones and at the finish.
Questions to ask before you hire
- Did you do a load calculation, or are you matching the size of the old unit?
- Is the furnace you're quoting set up or derated for our altitude?
- What venting, duct and gas line changes are included?
- Which refrigerant does the new system use, and how easy is it to service?
- What do the manufacturer and labor warranties cover, and do I need to register the equipment?
Heating and Cooling questions
Do I need a permit to replace my furnace or AC?
Usually, yes. Most replacements need a permit and inspection from your town or Douglas County, especially when gas, venting or electrical work is involved. The contractor you hire pulls it.
Will a heat pump keep up in a Douglas County winter?
Cold-climate heat pumps are built to keep heating in cold weather. Some homeowners keep a gas furnace as backup for the coldest nights. Ask each bidder how their system performs at low temperatures and at our altitude.
Should I replace the furnace and AC together?
It often makes sense when both are aging, because the indoor and outdoor parts are designed to work as a matched set and one install covers both. If one is much newer, replacing only the failed unit can be fine. We can scope both options.
My furnace quit tonight. Can you help?
Not tonight. DougCO Builds handles planned replacements, not emergency service calls, so call an HVAC company that offers emergency repair to get the heat back on. If the repair turns into a replacement, we can scope it so you aren't choosing under pressure.
