The house finally looks like a house again on the inside. When I walked through earlier this month the walls had insulation in them, new windows were in, and the new back porch was up. It’s been almost a year since the last journal entry, when the permit was issued and the crew had just dug the first footings in the basement.
Insulation
The exterior walls are now filled with closed cell spray foam insulation, which also seals the air gaps and creates a tight building envelope needed to make an all-electric house work. Heat pumps don’t work as hard when the heated or cooled air stays inside.
Some interior walls got fiberglass batts as an inexpensive way to modestly improve noise isolation.
The basement unit
The basement is now framed out for the third unit. Before the framing went up, the crew covered the foundation walls with a dimpled drainage membrane (the black sheets). The dimples create a small air gap so any moisture that comes through the brick runs down to the drain tile under the floor instead of soaking into the drywall.
Back porch
The new wood back porch is built and the stairs are in. The crew was still working around its base, and the yard is a mess of gravel, lumber, and wheelbarrows.
Drywall is coming next, but before that I hired an inspector to perform a “whole house” blower door test to find areas where the spray foam was insufficiently applied. Once the drywall, windows, and final doors are installed then the same inspector will return and do a blower door test in each dwelling unit. The ComEd Electric Homes program requires that the house passes all three tests.
I don’t feel like explaining the ups and downs of the last six months, which is when my building permit application was resubmitted. I’ll commemorate the occasion by sharing these photos of the new footings that have been excavated.
A new steel beam – actually three segments – will be installed in the basement, supported by two new posts on these two new footings. The orange lines in the footing holes represent the top of the future floor slab, indicating a 18″ dig-down.
The holes cannot be filled in until a city building inspector comes by. After they are filled in, and a post is installed, more excavation will occur on the perimeter to do underpinning. This will extend the depth of the house’s foundation to support it for another one hundred years, and probably prevent more sinking and shifting.
It’s been nearly two years since I’ve written a blog post about the gut rehab of the two-flat I bought in 2020 so I figured an update was necessary. The status is that I’m working on finalizing a contract with a general contractor and I have a loan application in progress.Read the other two-flat journal posts.
Two-flats – and their cousins the three- and four-flats – are the second most common building type in Chicago. There are approximately 254,800 homes in 2-to-4 flats in Chicago, according to data collected by the Cook County Assessor’s Office. And according to the U.S. Census they make up 27.2 percent of residential structures in Chicago. That’s compared to 25.5 percent detached homes, 3.8 percent attached homes, and 43.5 percent of houses, apartment, and condo buildings with five or more units (2-to-4 flats can also be condo buildings).
Thus it makes sense that there would be a handful of blogs to discuss their renovation.
(Although in the same vein it would probably make sense that there are blogs to discuss renovating condos, and I haven’t come across those.)
That’s my house on the left, captured in December 2024.
I’m glad each one of these is pretty well-organized because it takes a lot of time to peruse a project-oriented blog for specific information if you haven’t read it from the beginning.
Here are the blogs
Most recently updated is listed first.
Two Flat: Remade This is the story of a deconversion (to a single detached house) but the renovation process is pretty much the same as restoring two units; gas service remains in the house. By Matt and Sarah, who bought the house circa 2011 and are still renovating it (check out “The Plan” page to learn about their phasing).
Reshaping our Footprint (One Watt at a Time) Follow our journey of a deep energy retrofit (or energy efficient rehab) on a 100+ year old masonry two flat in Chicago. The goal is to turn the building into a zero-energy home with a sustainable and resource-efficient landscape. Most posts are by Marcus de la Fleur.
Yellow Brick Home Kim and Scott bought the dilapidated two-flat in 2019 and completed the renovation in 2021 or 2022. Each unit and the outside are detailed in three groups of articles. Yellow Brick Home is the most design-forward of the blogs.
Little Chicago Two Flat Corey and Emily bought their two-flat in 2021 and did a DIY renovation over the next eight months.
If you know of another blog about renovating a 2-to-4 flat in Chicago, leave a comment with the link!
Bonus links
Back To The Studs This a video series by Brad and Sean who have been renovating a Brooklyn brownstone into three units since 2021. I’ve been watching their progress on TikTok, but given the “soft ban” it’s better to look at their YouTube page.
Home electrification case study in North Lawndale “Through Elevate’s electrification program, contractors installed electric, energy efficient appliances at Ms. McGee’s house in Lawndale. The upgrades included an electric stove, washer and dryer, as well as a heat pump that powers a central heating and cooling system.”
Over the years I waffled once or twice about adding a third unit, in the basement. I hired a structural engineer to draw up plans for the replacement center beam in the basement’s ceiling. To “future proof” the plans, I also asked him to draw a plan and create specifications for a floor excavation in order to achieve a code-compliant ceiling height in the potential basement unit.
The basement, looking towards the front entry. Notice how smooth the floor is.
The waffling was based on the cost of the necessary digging down. Excavation will add about $25,000 to the cost of the project. (That’s based on one bid, the only bid that called it out specifically. I asked all three bidders to separate the costs of the basement unit so that I would know exactly how much the basement unit – excavation, walls, finishes, etc. – would cost as an “add on”.)
I think my architect also helped convince me to design and get bids for a third unit because of the flexibility it could provide for me and my tenants (which may include one or more family members), as well as the possibility of additional rental income.
I’ve settled on adding the third unit, and I’m excited to do it, in part because of my well-known enthusiasm for accessory dwelling units. (A note about Chicago’s ADU ordinance: this property is outside the ADU pilot area but it has unused zoning capacity per both the FAR and minimum lot area per unit standards so the additional unit is allowed without the ADU ordinance.)
Excavation
The Chicago Building Code requires that the ceiling height be a minimum of 7′-6″ in most of any dwelling unit (that’s measured from the finished floor to the finished ceiling). A limited amount of area is allowed to be lower to get around existing or newly installed pipes and ducts in the ceiling.
To achieve that, crews will demolish and remove the existing floor slab (which I’ll be a little sad about because the previous owner did a nice job pouring it) and excavating earth 10″ down. They’ll also underpin the foundation walls in an alternating pattern of rectangles around the perimeter. I hope I can explain underpinning well (otherwise watch Darren Voros’s video): This means they’ll dig under half of the foundation dispersed around the perimeter (the A sections), leaving unexcavated space between each to hold up the other half of the foundation (the B sections); then they’ll switch and repeat the process for the B sections.
A foundation wall detail showing the 10″ of excavation and the addition of a perimeter drain tile.
Water
After every rain storm I go and check the house. The basement has been dry every time. I’m surprised, and thankful, that it seems that water doesn’t seep into the basement.
One time I noticed that there was water pooling on the basement floor – when a rain storm had not occurred. It turned out that when I closed the water service line I didn’t close it well enough and water was very slowly leaking out. Tightening the valve handle was a simple resolution.
During the excavation there will be a perimeter drain tile system installed under the floor slab to steer water toward an ejector pit. An ejector pit is different than a sump pump in that it has a mechanism to grind the house’s sewage before pumping it to the city’s sewer main. I believe an ejector pit is a requirement when the lowest dwelling unit’s plumbing (i.e. the toilet) will be below the city sewer main.
Bob Vila’s website describes interior drains like this:
Similar to exterior drain tile, an interior French drain features a perforated pipe that carries water to a collection pit where it can be pumped to the surface. This type of drain is located along the interior perimeter of the basement and lies below floor level.
All You Need to Know About Basement Drains, Glenda Taylor and Bob Vila
Apartment
The new dwelling unit is drawn as a 1-bedroom apartment with a small bedroom that has two short windows and a closet. It has a large, combined living room, dining room, and kitchen.
The entryway is partially separated from the big room using a hall closet, creating a sort of mud hall. The bathroom is of a typical size for small apartments in Chicago and there’s a considerably sized utility room for laundry and storage. Overall, the apartment has an area of about 720 s.f.
I believe in-unit storage to be an important amenity. My current apartment is a studio and I selected it in part because it had good layout with a lot of scattered storage (there’s a walk-in closet, a large nook between the living area and the bathroom, a small closet, and a linen closet in the bathroom).
When I was looking for a new place to live in 2022 I didn’t want to have to move any of my stuff into a storage locker in the building or a storage unit in another building.
Other space in the basement
The rest of the basement, about 100 s.f., will have two hybrid heat pump water heaters, the ejector pit, electrical panels, and a little bit of room for storage. There’s also a rear entryway and the basement apartment will have a rear exit through here.
My architect has issued architectural plans for bidding!
(This happened a month ago, and I don’t dedicate enough time weekly to send the bidding instructions to general contractors and to follow up with them asking if they’re still planning to send a bid.)
The house is one block away from the Kedzie Green Line station, which offers a 20-minute ride to downtown or to Oak Park. Behind the station is The Hatchery, a major shared commercial kitchen and food business incubator.
The Cook County Land Bank Authority owns several properties on the block and is marketing these to developers for new housing.
I’ve already had a few GCs walk through the house and tell me they’re going to submit a bid. I found them either by asking architects I know, and by scouring the Building Permits Browser on Chicago Cityscape.
I filtered the permits, looking for “renovation/alteration”, set the estimated project cost from $100,000 to $400,000, and then skimmed the project descriptions for words like “two-flat” and “rehab”.
I made a list of those contractors and found their phone numbers and emails elsewhere (the city used to include their phone numbers in the building permits dataset, and took it out in 2019 or 2020).
This photo gives you a glimpse of some of the exterior issues (look at the cornice, especially at the far left corner). All of the windows and doors are proposed to be replaced. The awning will be removed eventually (it helps keep the snow off the front porch).
