ZigaForm version 7.6.7

Zoning Q&A

Zoning Suitability Checklist

Is zoning right for your home — and your equipment?

Zoning can improve comfort, but only when the home and system are designed for it. Use this checklist before agreeing to zoning.

Step 1: Home Layout & Comfort Problems

Check all that apply:

☐ Two-story home with temperature differences
☐ Large open areas mixed with small rooms
☐ Rooms that are consistently too hot or too cold
☐ Bedrooms used at different times than living areas
☐ Finished basement or bonus room over garage

➡️ If you checked none, zoning may not provide much benefit.

Step 2: Existing Duct System
Zoning depends heavily on duct design.

☐ Multiple trunk lines already exist
☐ Adequate return air in each zone
☐ Ducts are accessible (basement, attic, crawlspace)
☐ No history of high static pressure issues

⚠️ Red flag:

Single large trunk serving the entire house

Limited or undersized return air

Step 3: Equipment Compatibility (Critical)

This is where most zoning problems happen.

What type of system is being proposed?

☐ Single-stage AC
☐ Two-stage AC
☐ Variable-speed / inverter system

Important guidance:

❌ Single-stage systems are poor candidates for zoning

⚠️ Two-stage systems can work, but with limitations

✅ Variable-speed systems are best suited for zoning

If zoning is proposed with a single-stage system, ask why.

Step 4: Return Air Evaluation

Proper return air is mandatory for zoning.

☐ Each zone has its own return path
☐ Return sizing was calculated, not guessed
☐ Contractor discussed pressure relief or bypass strategies

⚠️ Zoning without adequate return air can cause:

Excessive noise

Short equipment life

Comfort complaints

Efficiency loss

Step 5: Contractor Design Process

Ask your contractor:

☐ Was a load calculation performed for each zone?
☐ How will static pressure be managed?
☐ What happens when only one zone calls?
☐ How will humidity be controlled?

If these answers are vague, zoning may be sold — not designed.

Bottom Line

Zoning is not a product.
It’s a system design choice.

When done correctly, zoning can greatly improve comfort.
When done incorrectly, it creates noise, inefficiency, and premature failure.