Healthy Home Checklist

This is not about perfection. It's about finding the biggest issues in your home and fixing the easiest ones first. Most people discover that a handful of changes, many of them free, make a measurable difference in their sleeping environment and air quality.

The checklist is organized room by room, starting where it counts most. The items draw from the 25 principles of building biology and the SBM-2008 testing standard, and they're prioritized by impact. The bedroom comes first because you spend a third of your life there and because sleep is when your body is least able to compensate for what's happening around it. Within each room, highest-impact actions are listed first.

Difficulty and Cost Guide

Bedroom. Highest Priority

Your body is at rest for eight hours. Your nervous system shifts into parasympathetic mode. Repair processes are running. Exposures that you might tolerate during the day become significant when they persist all night, uninterrupted. Every certified building biologist starts the assessment here, and so should you.

EMF: Electric and Magnetic Fields

• Measure magnetic fields at pillow height. Use a gaussmeter or a TriField TF2 set to magnetic mode. Sweep slowly across the entire bed surface at mattress height. Target: below 0.2 mG (the SBM-2008 "No Concern" threshold). Elevated readings often trace to wiring errors, nearby electrical panels, or high-current appliance circuits on the other side of the wall. $$ / Easy, requires meter (~$175 for TF2).
• Measure body voltage lying in bed. Connect a multimeter (set to AC millivolts) to a grounding rod driven into the earth outside. Hold a metal probe while lying in your normal sleeping position. Target: below 10 mV. This tells you how much AC electric field your body is absorbing from surrounding wiring and plugged-in devices. For the full procedure, see the EMF assessment guide. $$ / Moderate, requires multimeter and grounding rod (~$100–200).
• Check RF levels. WiFi router location, phone at bedside. A WiFi router in or near the bedroom is the dominant indoor RF source in most homes. Measure with an RF meter if available; at minimum, note how close the router is to the bed. A router one metre away can exceed the SBM-2008 "Extreme Concern" threshold of 1,000 µW/m². $ / Easy if relocating the router; $$ if purchasing an RF meter.
• Install a demand switch on the bedroom circuit. A demand switch (also called a circuit cut-off switch) automatically disconnects voltage from the bedroom wiring when no current is being drawn, typically when the last light is turned off. With voltage removed from the wires in the walls, body voltage drops dramatically. This is one of the most effective single interventions for the sleeping environment. $$$ / Professional, requires a licensed electrician (~$200–400 installed).
• Move or unplug all electronics within 1 metre of the bed. Phone chargers, bedside lamps, clock radios, extension cords, even when switched off, any cable carrying voltage radiates an electric field. Unplugging (not just switching off) eliminates the field from that cable. Move what you can't unplug farther from the bed. $ / Easy, free.
• Phone on airplane mode at night. A smartphone on the nightstand in normal mode transmits RF throughout the night as it communicates with cell towers, syncs data, and checks for notifications. Airplane mode stops all wireless transmission. The alarm still works. $ / Easy, free.
• Check mattress for magnetized springs. Steel innerspring coils can become permanently magnetized, creating a static magnetic field distortion at the sleeping surface. Test with a simple compass: hold it at mattress height and move it slowly across the surface. The needle should point consistently north. If it deflects or spins, the springs are magnetized. Consider a natural latex, wool, or cotton mattress as a replacement. $ / Easy to test; $$$ if replacing the mattress.

Bedding and Materials

• Use natural bedding materials. Synthetic fabrics (polyester, nylon, acrylic) generate static charge, don't breathe well, and may contain flame retardants or finishing chemicals. Cotton, wool, linen, and silk are breathable, regulate moisture, and don't build up static fields. Organic options avoid pesticide residues in the fibre itself. $$ / Easy.

Air Quality and Climate

• Install a CO₂ monitor and check morning readings. A closed bedroom with one or two occupants can exceed 2,000 ppm of CO₂ by morning, causing grogginess, poor sleep quality, and impaired cognition. Target: below 600 ppm (SBM-2008 threshold). A reading above 1,000 ppm means the room needs more ventilation, a cracked window, trickle vent, or mechanical ventilation. $$ / Easy. CO₂ monitors run $50–100.
• Maintain humidity between 40–60%. Below 40%, mucous membranes dry out and airborne virus transmission increases. Above 60%, dust mites proliferate and mold risk rises. A $15 hygrometer on the nightstand tells you where you stand. If humidity is persistently high, improve ventilation or run a dehumidifier. If persistently low, a simple evaporative humidifier helps. $ / Easy.
• Bedroom temperature: 16–18°C (61–64°F) for sleep. Core body temperature drops during sleep, and a cool room supports that. Research consistently shows improved sleep quality and duration in this range. A warm bedroom (above 21°C) fragments sleep and reduces time in deep sleep stages. $ / Easy, adjust thermostat or open a window.

Once the bedroom is addressed, move outward. The kitchen is next, it concentrates combustion byproducts, moisture, and high-current appliances in a small space.

Kitchen

Combustion byproducts, moisture, and high-current appliances, all in a small room. The priority here is ventilation and combustion safety.

• Check for gas appliance leaks and combustion byproducts. Gas stoves, ovens, and water heaters produce carbon monoxide (CO), nitrogen dioxide (NO₂), and formaldehyde during combustion. Even without a leak, normal operation of a gas stove without adequate ventilation can push NO₂ above outdoor air quality standards. If you have gas appliances, install a CO detector in the kitchen (required by code in many jurisdictions but often missing). Consider having your gas lines tested for leaks, the utility company will often do this free of charge. $ / Easy for CO detector (~$25); free for utility leak check.
• Ventilation hood vented to outside. A recirculating range hood filters grease particles but does nothing for CO, NO₂, moisture, or combustion byproducts. A hood that vents to the outside removes these at the source. If your hood recirculates, upgrading to a ducted exhaust hood is one of the highest-impact kitchen changes. Use it every time you cook, not just when something is smoking. $$ to $$$ / Moderate to Professional, depends on existing ductwork.
• Check under the sink for moisture and mold. The under-sink cabinet is the most common site for hidden kitchen water damage. Pull everything out and inspect the back wall, floor, and pipe connections. Look for discolouration, warping, soft spots, or musty odour. Slow leaks can run for months before they're noticed. Repair any leaks and clean or replace water-damaged materials. For guidance on mold assessment, see the mold testing guide. $ / Easy to inspect; cost of repair varies.
• Induction cooktop: maintain 30 cm distance during use. Induction cooktops generate strong magnetic fields at the surface to heat ferromagnetic cookware. At the cooktop surface, fields can reach 20–40 mG, well above the SBM-2008 thresholds. These fields drop rapidly with distance. At 30 cm, exposure falls to levels comparable to other kitchen appliances. Don't lean against the cooktop while stirring. $ / Easy, behavioural change only.

Living Areas

You may spend four to eight hours a day in living spaces, reading, working from home, watching television. Shorter exposure than the bedroom, but several common living room items are major RF and dirty electricity sources.

• WiFi router: consider wired Ethernet; at minimum, move the router away from seating areas. Switching to wired Ethernet and disabling the WiFi radio is the single most effective RF reduction in most homes. If that's not practical, relocate the router to a room where people don't sit for hours. Every metre of distance reduces exposure. Even moving the router from behind the couch to the opposite side of the room makes a measurable difference. $ to $$ / Easy to Moderate. Ethernet cables and a switch cost $30–80; running cables through walls may need more effort.
• Replace DECT cordless phones with corded phones. DECT base stations transmit RF continuously, 24 hours a day, whether or not anyone is on a call. Many people don't realize their cordless phone base is one of the strongest RF sources in the home. A corded phone produces zero RF. $ / Easy, corded phones cost $15–30.
• Check for dirty electricity near dimmers, LED, and CFL bulbs. Dimmer switches (especially older triac-type dimmers) and cheap LED or CFL bulbs with poor power-factor-corrected drivers inject high-frequency voltage transients onto your home's wiring. A Stetzerizer meter ($100) plugged into any outlet reads the level in Graham-Stetzer units. Target: below 20 GS in occupied rooms. If elevated, replacing the dimmer with a standard switch or swapping to higher-quality LED bulbs often solves the problem. $$ / Moderate.
• Natural flooring where possible. Vinyl plank (LVP), vinyl sheet, and PVC-based flooring can off-gas phthalates and other plasticizers, particularly when new or when heated by sunlight or radiant floor systems. Solid hardwood, natural linoleum, stone, tile, and cork are building-biology-preferred alternatives. If replacing flooring isn't feasible, good ventilation and time (off-gassing decreases over months to years) reduce exposure. For material guidance, see non-toxic building materials. $$$ / Professional for installation; $ for ventilation improvements.

Bathroom

Bathrooms produce more moisture per square metre than any other room. The priority is keeping that moisture from feeding mold or damaging structure.

• Ventilation fan working and properly vented to the outside. A bathroom exhaust fan should vent through a duct to the exterior of the building, not into the attic, soffit, or wall cavity. Venting into the attic is a common code violation that leads to mold growth on roof sheathing. Test your fan: hold a tissue near the grille while it's running, it should pull the tissue flat. If the tissue flutters weakly, the fan may be undersized, the duct may be blocked, or the fan motor may be failing. Run the fan for at least 20 minutes after showering. $ / Easy to test; $$ to $$$ if ductwork needs correction.
• Check caulk and grout for mold. Silicone caulk around tubs, showers, and sinks deteriorates over time. Once it cracks or pulls away from the surface, water penetrates behind it and mold colonizes the gap. Dark discolouration in grout lines or along caulk joints is usually mold. Remove and replace failed caulk. Re-grout or seal grout lines that are cracked or perpetually damp. $ / Easy, caulk costs a few dollars; application takes 30 minutes.
• Control humidity after bathing. Bathroom humidity can spike above 90% during a shower. Without adequate ventilation, this moisture migrates into walls, ceilings, and adjacent rooms. Beyond running the exhaust fan, wipe down shower walls after use, leave the shower door or curtain open to allow surfaces to dry, and keep the bathroom door open once you've finished (if the exhaust fan is running) to let drier air from the rest of the house assist drying. $ / Easy, behavioural change.

Whole House

These items apply to the home as a whole. Radon, water quality, and HVAC filtration affect every room and every occupant.

Air Quality

• Radon test at the lowest occupied level. Radon is a naturally occurring radioactive gas that enters homes through the foundation. It is the second leading cause of lung cancer after smoking. Every home should be tested, radon levels are highly localized and cannot be predicted by neighbourhood or building type. Use a long-term alpha track detector (90+ days) for the most accurate result. Place it in the lowest level where anyone spends time. The EPA action level is 4 pCi/L; building biology targets are lower. For detailed instructions, see the radon testing guide. $ / Easy, long-term test kits cost $15–25.
• Upgrade HVAC filter to MERV 13 if the system supports it. Standard fibreglass filters (MERV 1–4) catch large debris but let fine particulate matter, mold spores, and allergens recirculate. MERV 13 filters capture particles down to 0.3 microns, including most mold spores, bacteria, and fine dust. Check your system's specifications first, some older systems can't handle the higher pressure drop without reduced airflow. Replace filters on schedule (every 90 days for most systems, monthly if you have pets or allergies). $ / Easy. MERV 13 filters cost $15–30 each.
• Test for formaldehyde if you have new furniture, flooring, or cabinets. Pressed wood products. MDF, particleboard, plywood with urea-formaldehyde binders, are the primary source of indoor formaldehyde. New cabinets, laminate flooring, and flat-pack furniture can off-gas for months to years. The SBM-2008 flags formaldehyde above 20 µg/m³. Inexpensive passive test badges ($30–50) measure average exposure over several days. For testing methods, see VOC and formaldehyde testing. $$ / Easy.
• Review cleaning products, switch to low-VOC options. Conventional cleaning products are a significant source of indoor VOCs, including fragrances (which can contain dozens of undisclosed chemicals), chlorine, ammonia, and glycol ethers. Fragrance-free, plant-based cleaners with disclosed ingredients do the same job without the off-gassing. Vinegar, baking soda, and castile soap handle most household cleaning. The simplest rule: if it has a strong chemical smell, it's adding VOCs to your indoor air. $ / Easy.

Water

• Test your water quality. Municipal water reports tell you what leaves the treatment plant, not what arrives at your tap. Lead from old solder joints, copper from corroded pipes, and disinfection byproducts that form in the distribution system all vary by household. A basic water test panel from a certified lab costs $30–100 and covers lead, copper, nitrates, and coliform bacteria. Homes with well water should also test for arsenic, iron, manganese, and pH. Based on results, a point-of-use carbon block filter or reverse osmosis system addresses most common contaminants. $$ / Easy.

Electrical

• Check the electrical panel for wiring errors. Wiring errors, shared neutrals across circuits, reversed hot/neutral connections, bootleg grounds, create net current conditions that produce elevated magnetic fields throughout the home. These fields can't be shielded. If your magnetic field readings are above 1 mG and persist when appliances are off, wiring errors are a likely cause. Hire an electrician experienced with building biology assessments (or a certified building biologist) to inspect the panel and trace affected circuits. $$$ / Professional.

How to Prioritize

If you're looking at this checklist and wondering where to start:

1. Start with the bedroom. The items that cost nothing, unplugging devices near the bed, phone on airplane mode, adjusting temperature, take five minutes.
2. Test what you can measure. A CO₂ monitor, a radon test kit, and a basic EMF meter give you data instead of guesses. You can't fix what you can't quantify. The EMF meters buying guide covers equipment selection in detail.
3. Fix the easiest high-impact items first. Moving the WiFi router, replacing a DECT phone, improving bathroom ventilation, and upgrading the HVAC filter are all low-cost changes with measurable outcomes.
4. Address the bigger items with professional help. Demand switches, wiring error corrections, ducted range hoods, and radon mitigation systems are worth the investment but require skilled installers.
5. Re-measure after each change. The only way to confirm an intervention worked is to measure the same parameter again. Magnetic fields were 1.5 mG before and 0.1 mG after the electrician corrected a wiring error? That's evidence. Nothing changed? Keep looking.

Seasonal and Periodic Checks

Some conditions change with the seasons, with occupancy, or as materials and systems age.

• Every month: Check HVAC filter. Inspect bathroom caulk and grout. Review humidity levels.
• Every season: Run the bathroom exhaust fan and check airflow. Inspect under-sink areas for leaks. Check CO₂ levels (ventilation patterns shift between heating and cooling seasons).
• Annually: Re-test radon (levels can change year to year). Check range hood ductwork for blockages. Review cleaning product inventory. Test smoke and CO detectors.
• After any renovation: Test for formaldehyde and VOCs if new materials were installed. Re-measure EMF if electrical work was done. Check that ventilation pathways weren't blocked.

When to Call a Professional

Most items here are accessible without special training. But some situations call for professional assessment:

• Elevated magnetic fields you can't trace to a source, a building biologist with a data-logging meter can capture 24-hour patterns and identify wiring errors that a spot measurement misses.
• External RF from cell towers or smart meters, shielding is effective but must be done correctly. Improper shielding traps RF inside the home and can make things worse.
• Visible mold beyond a small surface patch, disturbing mold without proper containment spreads spores throughout the home. Professional remediation is warranted for anything larger than a few square feet.
• Persistent symptoms you suspect are environment-related, a certified building biologist assesses all exposure categories (EMF, air quality, moisture, materials, acoustics) using calibrated instruments and can identify interactions that single-parameter testing misses.

To find a certified practitioner in your area, see the building biologist directory.

You don't need to do everything at once. Start with the bedroom, even just unplugging devices and switching your phone to airplane mode. Once that room is better, work outward at whatever pace makes sense.