TradesQuote Blog
- 26 Jun, 2026
Commercial HVAC Tons per Square Foot (Sizing Guide)
Commercial HVAC sizing by square feet per ton, with planning figures for offices, retail, restaurants, warehouses, and server rooms - why internal gains dominate and why a block load calc is required.
- 26 Jun, 2026
Duct Size Chart: How to Match Duct Size to CFM
A round duct size chart by CFM, what a ductulator actually does, the friction-rate and velocity rules behind it, how to convert round to rectangular, and how to size supply vs return ducts.
- 26 Jun, 2026
Furnace and AC Replacement Cost (Replacing Both Together)
What it costs to replace a furnace and air conditioner together: combined price ranges by efficiency tier, why a matched system is worth it, the cost breakdown, and when to replace just one.
- 26 Jun, 2026
Heat Load & Cooling Load Calculation: How It Works
How an HVAC load calculation - also called an air conditioning load or AC load calculation - works: the heat-loss formula Q = U × A × ΔT, the sensible and latent parts of a cooling load, a worked residential example, and how to convert load to tonnage.
- 26 Jun, 2026
Will a Higher SEER Save You Money? The Real Math
How much a higher-SEER air conditioner actually saves on your bill, the formula linking SEER to annual cost, a cost-by-rating comparison, and the payback math that decides whether the upgrade is worth it.
- 26 Jun, 2026
HVAC Labor Rate: How to Set Your Hourly Rate
How HVAC contractors set a billable labor rate that actually makes money - the loaded-rate formula, labor burden, overhead, billable-hour reality, flat-rate vs T&M, and a worked example.
- 26 Jun, 2026
How Much Does a New HVAC System Cost in 2026?
Installed cost ranges for central AC, furnaces, heat pumps, and full systems in 2026 by size, efficiency tier, and region. What drives the price up or down, plus tax credits.
- 26 Jun, 2026
Return Air Duct Sizing: How to Size the Return Side
How to size return air ducts: why returns must match supply airflow, a return duct size chart by CFM, single vs multiple returns, filter grille sizing, and the static-pressure problems undersizing causes.
- 26 Jun, 2026
What Size Mini Split Do I Need? (Sizing Chart)
How to size a ductless mini split: a BTU-by-room-size chart, single-zone vs multi-zone sizing, why oversizing wrecks an inverter, and the adjustments that change the number.
- 25 Jun, 2026
Essential HVAC Formulas Every Tech Should Know
The core HVAC formulas in one place: sensible and latent heat, total heat, CFM, tonnage, delta T, static pressure, SEER/EER, and the constants behind them, with worked examples.
- 24 Jun, 2026
How Much Does Furnace Replacement Cost? (2026)
What a new furnace costs to install: price by size, fuel type, and AFUE efficiency, the factors that move the total, repair vs replace, and how to estimate your job.
- 23 Jun, 2026
How Much Does It Cost to Run Central AC?
What central air costs to run per hour, day, and month. The formula tying tonnage, SEER2, and electricity rates to your bill, plus worked examples and ways to cut cooling costs.
- 22 Jun, 2026
EER vs SEER vs SEER2: What Each Rating Means
EER, SEER, and SEER2 all measure AC efficiency differently. What each one means, how they're calculated, how to convert between them, and what counts as a good rating.
- 21 Jun, 2026
How Much Does Central Air Installation Cost? (2026)
What it costs to install or replace central air conditioning: price by tonnage and SEER2, the factors that move the total, install vs replacement, and how to estimate your job.
- 20 Jun, 2026
Dew Point and HVAC: Why It Matters in Duct Design
What dew point is, why ducts sweat and grow mold when surfaces drop below it, the comfort thresholds that feel muggy, and how insulation and vapor barriers prevent condensation.
- 20 Jun, 2026
How to Estimate an HVAC Job: A Contractor's Pricing Guide
A step-by-step way to estimate and price HVAC jobs: counting true job costs, applying the right markup/margin, building an accurate quote, and avoiding the estimating mistakes that kill profit.
- 19 Jun, 2026
What Is Manual J? Heat & Cooling Load Calculation Explained
Manual J is the ACCA standard for calculating a home's heating and cooling load. What it is, the inputs it uses, how heat load and cooling load are calculated, and why it beats rules of thumb.
- 18 Jun, 2026
How Much Does Ductwork Replacement Cost? (2026 Pricing)
What new or replacement ductwork costs - by the foot, by the run, and for a whole house. The factors that move the price, repair vs full replacement, and how to estimate your job.
- 18 Jun, 2026
How to Size a Dehumidifier for Your Home
How to size a dehumidifier by square footage and dampness level, what the 2019 DOE pint rating change means, and when to choose a whole-house unit over a portable.
- 17 Jun, 2026
BTU per Square Foot for Air Conditioning: The Chart and the Math
How many BTU per square foot you need for cooling, with a room-size chart, the climate adjustments that change the number, and why 20 BTU/sq ft is only a starting point.