25 Jun Keep Tenants Happy in Summer: 10 Tips for St. Louis Landlords

St. Louis summer is a stress test for a rental house. Ninety-degree afternoons, damp basements, storms that fill the sump pit, and a lawn that won’t quit. Tenants don’t renew because you hosted a barbecue; they renew because the AC worked in July and you fixed things before they called. Here are the ten things we do on every single-family and small-multifamily rental we manage between May and September.

1. Service the air conditioner before the first 90-degree stretch

Book an HVAC tune-up in April or early May, before the season’s first heat wave fills every technician’s calendar. That means checking refrigerant, cleaning the condenser coil, testing the capacitor, and clearing the condensate drain, the most common summer service call we see.

There’s a legal reason too. Missouri law requires landlords to provide heat but says nothing about cooling. The City of St. Louis changed that with Ordinance 71839, the “Safe Temperatures in Rentals” ordinance passed in 2024. City rental units must be capable of holding an indoor temperature between 68 and 85 degrees in at least one habitable room from May 1 through September 30, and throughout the unit from June 1 through September 30. If you provide a cooling system, it must be maintained so it can keep every room at 85 or below, you must tell tenants how to use it and how to report problems, and you can’t retaliate against a tenant who reports you. Fines run up to $500 per day. Even outside the city limits, a dead AC in July is the fastest way to lose a good tenant.

2. Help tenants manage Ameren’s summer rates

Ameren Missouri bills its higher summer electric rate for the June through September billing periods, and its time-of-use plans price weekday afternoons and early evenings highest. A one-page note at move-in explaining the summer season and Ameren’s rate options does more for satisfaction than any amenity. Make sure the lease is clear that electric and Spire gas service go in the tenant’s name from day one, and confirm the accounts actually transferred so you’re not paying July’s bill.

3. Get ahead of basement humidity

Most St. Louis rentals built before 1960 have a basement, and most of those basements smell in August. A dehumidifier set to about 50 percent, draining to a floor drain or the sump pit so nobody has to empty a bucket, prevents the mildew that tenants photograph and send you. Check that the dryer vents outside and that bathroom exhaust fans actually pull air.

4. Test the sump pump before storm season

Summer storms here drop inches of rain in an hour. Pour a bucket of water into the sump pit and watch the pump cycle, check that the discharge line runs well away from the foundation, and consider a battery backup, because the pump fails exactly when the power does. The Metropolitan St. Louis Sewer District publishes backup-prevention guidance, and a backflow preventer is cheaper than a finished-basement claim.

5. Plan for pest season, not just pest calls

Three pests own a St. Louis summer. Subterranean termites swarm in spring, and the Missouri Department of Conservation notes they hollow wood from the inside with little outside sign; an annual inspection on older wood-frame houses is cheap insurance. Mosquitoes breed in anything that holds water for a week; the City of St. Louis Health Department asks owners to dump standing water weekly and offers fogging on request through the Citizens’ Service Bureau, and St. Louis County’s Vector-Borne Disease Prevention program covers unincorporated areas and contracted municipalities. Yellowjacket colonies reach their peak in late summer, and the German yellowjacket common here nests in wall voids and soffits; treat nests in July before they hit several thousand workers. Write into the lease who pays when an infestation traces back to housekeeping.

6. Keep the grass under the legal limit

The City of St. Louis Forestry Division enforces a seven-inch limit on grass and weeds; a notice gives you ten days before the city mows and bills you the abatement plus a $100 fine. Unincorporated St. Louis County caps it at eight inches with seven days to cut after notice, and municipalities set their own, from seven inches in Kirkwood and University City to ten in Webster Groves. If the tenant mows, put the height and the frequency in the lease. If you’d rather not depend on that, a lawn service is cheaper than a citation.

7. Repair or replace window screens

Tenants open windows on the first cool evening in September, and a torn screen means mosquitoes inside and a complaint the next day. Walk the exterior in May, rescreen anything with holes, and confirm every operable window has one.

8. Check gutters and downspouts after the spring seed drop

By early June the maples and sweetgums have finished dumping seeds into every gutter in town. Clear them, make sure downspouts discharge at least a few feet from the foundation, and look for splash blocks that have wandered. It’s the cheapest way to keep water out of the basement. We keep gutter work on the owner’s side of the lease; tenants on ladders are a liability nobody wants.

9. Do a mid-lease check-in

Summer is the natural halfway point for a lease that started in winter. Schedule a short visit with proper notice: change the furnace and AC filter, test smoke and carbon monoxide alarms, look under sinks, and ask the tenant what’s bugging them. Small annoyances that never get reported, a sticking door or a slow drain, are what people remember when the renewal letter arrives. Fixing them now costs almost nothing.

10. Send renewal offers before the market decides for you

The St. Louis rental market is busiest from spring through late summer, which is when you want leases to end and when you want good tenants locked in for another year. Send renewal offers 60 to 90 days before expiration, price them against current comps, and give your best tenants your best terms. A tenant who has had a comfortable, dry, bug-free summer with a landlord who showed up is not shopping other listings. That’s the whole point of the nine tips above.

If this list looks like a lot of Saturdays, that’s because it is. Our property management team handles the tune-ups, inspections, vendors, and renewals for St. Louis owners so summer runs on a schedule instead of on emergencies. To see what your rental should be earning, check the St. Louis market report on Wizah or book a free consultation with one of our agents.