How to Check for Floor Sloping and Creaking in Rental Apartments—Key Points for Identifying Structural Issues During Viewings

Floor Slope and Creaking—Why They're Often Overlooked

When viewing rental apartments, people tend to focus on layout and storage space, but "floor condition" is one of the elements that renters most regret not paying more attention to. Floor slope and creaking aren't just uncomfortable—they can be signs of structural problems with the building.

Problems Caused by Floor Slope

Even minor slope can affect daily life.

Impacts on Daily Life

• •Objects and drinks on desks shift and fall
• •It's difficult to place furniture (dressers, bookshelves, beds) level
• •Balls and round objects roll away
• •Long-term living may cause dizziness or fatigue (affecting vestibular function)

Signs of Structural Problems

• •Foundation or ground settlement
• •Deterioration or warping of pillars and beams
• •Floor frame decay from termite damage
• •Construction defects (can occur even in new buildings)

Generally, a slope of 3/1,000 (3mm per meter) or greater may be recognized as a "building defect."

How to Check During a Viewing

Using Marbles and Level Apps

Place a marble you've brought on the flooring and note which direction it rolls. You can also use your smartphone's level app as an alternative, and slopes of ±0.5 degrees or more warrant careful attention.

Visual Inspection

• •Check if window and door frames are parallel (warping suggests the entire building may be sloped)
• •Check if flooring board seams are lifting
• •Step on the four corners and center of the room to check for differences in depression

Walking Test

Walk slowly through the entire room and feel for any slope. Pay particular attention to height differences between the center and edges of the floor.

Mechanisms and Types of Floor Creaking

Creaking (floor noise) is classified by its cause as follows:

Surface-Level Creaking (Easy to Address)

This is caused by flooring materials drying, shrinking, and expanding. It occurs most often when heating is used in winter. In some cases, injecting lubricant (anti-squeak spray) into flooring seams can improve the problem.

Structural Creaking (Requires Attention)

This creaking is caused by deterioration or warping of subflooring materials (floor joists and plywood). If creaking occurs every time you step in a particular spot and makes the same sound repeatedly, there may be a structural problem. Repair may sometimes require removing the flooring material.

Creaking from Termite Damage

This is a serious problem that commonly occurs on the first floor of single-family homes or wooden apartment buildings. If the floor feels soft and spongy when stepped on and there's a smell of decay, suspect termite damage.

Verifying and Negotiating with Your Management Company

If you notice floor slope or creaking during a viewing, respond using these methods:

Key Points to Verify and Ask

• •Ask about the previous tenant's reason for leaving (if they left due to floor problems, disclosure may be required)
• •Confirm the floor's repair history
• •Ask about termite treatment history (particularly important for wooden buildings over 15 years old)

Requesting Repairs Before Move-In

If creaking or slope is confirmed, you can negotiate to make repairs a condition of move-in. If repairs are difficult, it can also serve as grounds for rent negotiation (reduction).

Recording a Move-In Checklist

Always record existing damage and floor condition on a move-in checklist and take photos. This will serve as proof of whether damage existed before move-in or occurred during your tenancy.

What to Do If You Notice Issues After Move-In

If you discover slope or creaking after move-in, contact your management company in writing immediately. Verbal reports leave no record, so it's crucial to document this via email or messaging apps.

Equipment repairs in rental properties are the landlord's obligation (Civil Code Article 606). If slope is causing living difficulties, you have a legal right to request repairs. If repairs are refused or response is delayed, you can consult your prefecture's rental housing management registration office or consumer consultation center.

Summary

Floor slope and creaking are easily overlooked because you might think "I'll get used to it." However, if they indicate a structural problem, they directly affect your living environment and property value (rent level). If left unaddressed, there's risk of mold and termite damage spreading. Taking just five minutes to check the floor during a viewing can significantly reduce the risk of regret after you move in. Make it a habit to use a simple smartphone level app check.

Deteriorating water supply pipes and low water pressure in rental housing are problems often discovered only after moving in. A real estate rental expert explains in detail the signs of deterioration you can spot during a viewing, methods to check water pressure, and the cost-sharing rules when plumbing work is needed.