Apt.1 Laundry Room Vol.4: Partition Wall Base Treatment

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ud83dudcda Apt.1 Laundry Room Series u2014 4 of 8

u2190 Apt.1 Laundry Room Vol.3: Plasterboard Overlay u00b7 Series Index u00b7 Apt.1 Laundry Room Vol.5: Wallpaper Finishing u2192

u270fufe0f Originally published: January 3, 2022 / ud83dudd04 Updated: May 8, 2026

2026 DIY Dad’s Note: Creating the New Laundry Room & 2021 Year in Review
Building the Door Frame
Putty Treatment on the Opposite Wall
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2026 DIY Dad’s Note: Creating the New Laundry Room & 2021 Year in Review

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Re-caulk every 3u20135 years. Black mold on caulk is the #1 tenant complaint in Japan.

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Alongside the bathroom renovation, the laundry/changing room was built from scratch. 2021 was also a landmark year for DIY Dad as a landlord-renovator.

Creating the New Laundry Room (Partition Wall)

Apt.1 had a bathroom on the ground floor, but no dedicated laundry/changing room. A new partition wall was built to create one.

Partition wall installation steps:

Mark out the wall position (check for square and plumb)
Attach the bottom and top plates (runners) to the floor and ceiling
Install studs at regular intervals
Attach plasterboard to both faces
Fill joints and screw holes with putty
Finish with wallpaper

Building a partition wall is a major structural change to the floor plan u2014 but it’s fully achievable with DIY. The key is being thorough about checking vertical and horizontal alignment throughout.

Door Installation

For the laundry room entrance door:

Pre-hung door sets (door + frame as one unit) make installation much simpler
Bi-fold doors work well in tight changing room spaces
Sliding doors are space-efficient and easy to use

The flow from bathroom u2192 laundry room u2192 hallway directly affects livability. Think from the tenant’s perspective when designing the layout.

2021 in Review u2014 DIY Landlord Style

For DIY Dad, 2021 was the year of Apt.1’s major overhaul. Main work completed by hand:

2nd floor Japanese rooms (6-mat and 4.5-mat): full renovation of ceiling, walls, floors, and fittings
1st floor Japanese room, kitchen, toilet, bathroom, and laundry room
Staircase ceiling and wall painting
Various fixture replacements (toilet, bathtub, vanity, etc.)

Renovating a full apartment u2014 six units or so u2014 entirely by hand over the course of a year was an enormous experience, both in DIY skill and in the mindset of being a hands-on landlord.

Subfloor & Base Treatment for the Laundry Room

After the partition wall goes up, the interior base treatment:

Fill plasterboard joints with mesh tape, then putty
Extra waterproofing on the wall adjacent to the bathroom
Confirm supply and drain pipe positions for the vanity

Since this is a wet area, moisture-proofing the base layer is especially important. Take the time to do it right u2014 water problems after the fact are much harder to fix.

ud83cudfe2 Thinking About Apartment Investment or Renovation?

For apartment renovations, return on investment is everything. DIY Dad dramatically cuts costs by doing the work himself.

Marutoku Shop u2014 Renovation Materials & Timber Online u00bb

Hey there u2014 DIY Dad here! The 1st-floor laundry room renovation continues. Today: introducing the walls and lighting, then tearing out part of the old earthen wall to build a door frame from wood.

Where the new and old walls meet, the alignment won’t be perfectly flush u2014 there’s inevitably a slight step. That’s just the nature of the work. (The photos below show what I mean.)