A new small strip center in Southeastern Wisconsin needs about $40 a foot triple net to pencil, roughly three times the metro average asking rent. That gap protects most of your rent roll, and exposes the tenants who will pay for new.
At today's costs, a new small strip center in Southeastern Wisconsin needs about $40 a square foot, triple net, to be worth building. The metro's average asking retail rent is under a third of that. For most of your tenants, there is no new building coming to take them, and an owner who discounts rent to guard against new supply is paying for protection the construction market already gives away for free.
The gap has one hole, and it is shaped exactly like the tenants you most want to keep.
Build it on paper first
Here is what a developer has to believe to put up a 12,000 square foot strip today.
Hard cost: Rider Levett Bucknall's Q2 2026 cost report puts strip retail construction at $170 to $280 a square foot in Chicago, the nearest city it surveys. Use $200. Add our assumptions for land, site work, soft costs, tenant improvements, leasing commissions and carry, and the center costs about $4,646,700, or $387 a foot.
Yield on cost: a developer has to earn more building a center than it would earn buying one. Per Matthews, Midwest unanchored strips sold at an average 8.0% cap rate in the first half of 2025. Add a 150 basis point development margin, our assumption for the risk of building and leasing from scratch, and the target is 9.5%.
Now solve for rent. $4,646,700 at 9.5% is $441,436 of net operating income. Allow 5% for vacancy and credit loss and 3% for expenses the leases do not recover, and the rent comes out at $39.92 a foot, triple net.
- All-in cost
- $387/SF
- Yield on cost
- 9.5%
- Rent it needs
- $39.92 NNN
- Metro asking rent
- $13.64
Move the inputs and the answer moves, but not far enough to matter. With cheap land, $170 hard costs, lighter allowances and an 8.5% target, it is $28.67. At the top of the RLB range, $50.16. Every 50 basis points on the yield target is about $2.10 of rent. And the target is not drifting down: the 10-year Treasury ended Q2 2026 near 4.40%, per The Boulder Group, which keeps the cost of the money high too.
The moat rent
Call the number a new building needs the moat rent. The distance between it and your rent is your moat: how far the market would have to move before anyone could build a competitor next door.
Per Cushman & Wakefield and Boerke's Q1 2025 Milwaukee retail report, the metro's average asking rent was $13.64 triple net. Against a $39.92 moat rent, that is a moat of about $26.28 a foot. Put differently, rents would have to roughly triple before new small-shop space made sense for the average tenant. That average includes big boxes and tired space, and small shops in good centers rent above it, so use your own rent, not the metro's.
The width varies by submarket, and this is where it gets useful. The same report shows asking rents from $8.90 in Western Milwaukee to $27.56 in the North Shore, and BizTimes reported Wauwatosa at $29.88 in Q3 2024. In Western Milwaukee the moat is enormous. In the North Shore and Wauwatosa, rents are at or above the low-cost case of $28.67. That is where you should expect someone to build, and where the moat will not protect your rent.
So why do owners discount anyway? Because the threat is cheap to make. A tenant's broker can mention the new development on the highway at every renewal, and it costs nothing to say. Some of those projects are real. Most are a rendering, a sign on a field, or a building that will ask twice your rent if it ever opens. Before you give up a dollar a foot to that threat, ask what the new space is asking. Then compare it to the moat rent. A project that has not found its tenants at $39.92 is not competing with you at $15.
The pipeline confirms the math
The national numbers say developers ran the same arithmetic. CBRE reported 4.7 million square feet of U.S. retail completions in Q1 2026, the lowest since it began tracking in 2005, against more than 25 million in Q4 2015. Cushman & Wakefield put the active pipeline at less than 0.3% of existing inventory in Q2 2026, with 2.3 million square feet delivered that quarter, 82% of it neighborhood and strip product.
Locally, Cushman and Boerke counted 21,100 square feet under construction across a 30.9 million square foot Milwaukee market in Q1 2025, and noted that 98% of that quarter's leases were in Class B and C buildings because there was so little Class A space and so little new construction. One Milwaukee broker put it to BizTimes more bluntly in late 2024: tenants who expect a landlord to build for them are told, "No they won't, they absolutely will not."
National data is most of what exists, and the Milwaukee figures are from 2024 and early 2025. They agree: Southeastern Wisconsin is not building small-shop retail at scale, and the math says it will not until rents move a long way.
The tenants who will pay for new
The moat protects you from a tenant choosing new space over yours. It does not protect you from tenants for whom new space is worth $39.92.
Drive-thru restaurants. A drive-thru lane does sales per square foot an inline suite cannot, and the operator will pay for a pad or a build-to-suit to get it.
Medical and dental. Specialized buildouts, long terms, and operators who value parking, visibility and a new front door. Their occupancy cost math can absorb new-construction rent.
National credit on a new pad. A bank or a coffee chain choosing a corner will fund its own building rather than take your end cap.
What these tenants have in common: strong sales or strong credit, and a reason to want something your center cannot give them. They are also, usually, your best tenants. If you have one, the moat does not apply to that lease.
Lease like the moat is real
For everyone else, act on it.
- On renewals, price against market rent in the next-best existing space in your trade area, not against a new building that is not coming. That is the tenant's real alternative.
- Be careful with tenant improvement allowances to keep tenants who have nowhere new to go. Spend where the tenant has a real alternative.
- Protect the tenants who could leave for new product: the drive-thru operator, the dentist. Their renewal is where concessions are worth it.
- If you have spare land, you are the one who can offer new product. A pad in your own lot competes for exactly the tenants the moat misses.
Measure your moat
- Get a local hard cost opinion from a contractor, or use the RLB range for Chicago as a starting point.
- Add your own land, site, soft cost, allowance and carry assumptions.
- Multiply by a yield on cost: today's local cap rate plus a development margin.
- Divide by your leasable square feet, grossed up for vacancy and unrecovered expenses. That is your moat rent.
- Subtract your average in-place rent. That is your moat.
- List the tenants who would pay the moat rent for new space. Those are the renewals to worry about.
If you want the math run on your center and trade area, send it over.