Buying a Houston 3-story townhouse: what to check on each floor, from the slab to the roof deck

The expensive problems in a Houston 3-story townhouse are rarely on the floor you tour first. They are at the top, where a flat roof deck and a stack of windows take the full force of Gulf rain, and at the bottom, where the garage and a single bedroom sit lowest on a lot that may have been redrawn into the floodplain after Harvey. Check those 2 ends before you fall for the kitchen on the second floor.

What follows is a walk through the building in the order the water and the heat move through it: roof first, ground last, then the paperwork that governs the driveway you share with 3 neighbours.

Why Houston builds so many of these

The City of Houston has no conventional zoning. What it does have is a platting system that lets an inner-loop lot that once held one bungalow be split into narrow lots, each carrying its own tall, thin house. That is why Rice Military, the Washington corridor, Montrose and EaDo are lined with them. Land inner-loop is often worth more than the structure standing on it, so builders put the square footage into height rather than width.

That history explains most of the defects. These houses are built fast, in rows, by builders working to a price per square foot on a lot where every foot of width counts. Nobody is doing anything sinister. But the details that take time, like flashing a roof-deck door or sizing an air conditioner for the third floor rather than the whole house, are the details that get skipped when a row of 6 has to close by spring.

Start on the roof

Is a rooftop terrace a leak waiting to happen?

Not necessarily, but it is the most likely leak in the house. A roof deck is a flat or near-flat roof with people walking on it, a door cut into it, railing posts screwed through it and, often, an outdoor kitchen plumbed across it. Every one of those is a hole in the waterproofing.

What to look at:

• The door threshold. The door from the stair enclosure onto the deck should sit on a raised curb, with the membrane turned up behind it. A door that opens flush onto the deck surface, with nothing stopping water that ponds against it, is the single most common way these houses take on water.
• The railing posts. Posts bolted down through the membrane need a sealed boot at each one. Posts fixed to the side of a parapet avoid the problem entirely.
• Where the water goes. Find the drains or scuppers. Pour a bucket near the lowest corner if the seller lets you. Water that sits for more than a few minutes on a Houston roof in August is cooking the membrane.
• The ceiling directly below. Stains, fresh paint in one patch, or a ceiling that has been retextured in a single bedroom all deserve a question.

If the deck has an outdoor kitchen with a gas line and a sink, ask to see the permit for that work. It is sometimes added after closing on the first owner's behalf, by a different contractor, with no one checking the membrane afterwards.

The third floor

Why is the top floor always hotter and stickier than the rest of the house?

Heat rises, and in a 3-story house it has 3 floors to rise through. The top floor also sits right under the roof, and on most of these houses the attic above it has been sealed with spray foam on the underside of the roof deck. That keeps the attic cooler, but it also changes how much cooling the house actually needs.

Climate zone 2A is hot and humid, and the humidity is the part that matters. An air conditioner that is too large for the space cools it quickly, shuts off, and never runs long enough to pull the moisture out of the air. The result is a room at 72 degrees that still feels clammy. In a townhouse, the usual failure is a single system trying to serve 3 floors, or 2 systems where the one serving the top floor was sized by rule of thumb rather than by a Manual J load calculation. We covered why that sizing step decides the outcome in the piece on foaming the attic of an existing house.

How to check it without equipment: visit on a hot afternoon, not a mild morning. Stand in the top-floor bedroom. If the system runs in short bursts, a few minutes on and a few off, and the room feels damp, that is short-cycling. Ask how many systems the house has, which floors each serves, and whether the builder has the load calculation. Most will not have it to hand. The ones that do tend to have got the rest of the house right too.

Also look at the windows up here. A narrow house gets its light from the front and back, so the upper floors often carry tall walls of glass facing whichever way the lot happens to face. A west-facing third floor with floor-to-ceiling glass and no overhang will fight any air conditioner you put in it.

The middle floor

This is the floor that sells the house: the kitchen, the living room, often a small balcony. It is also the floor with the least to worry about. Check it like any house. Run the taps, open every window, look at the grout.

Two things are specific to the type.

First, count the stairs. At a typical floor-to-floor height, each flight is roughly 16 steps, which puts the primary bedroom on the third floor about 32 steps above the garage. Every bag of groceries climbs the first 16. That is fine for many buyers for many years, and it is a real reason some people sell sooner than they planned. A few builders stack a closet on each floor in the same position so an elevator can be added later. If the house you are looking at has that, it is worth a great deal more to some buyers than the listing will say. If you expect to stay into later life, Modern Acre Studio's piece on what a house you plan to grow old in has to get right is a useful list to hold against the plan.

Second, look at the balcony. It is a small version of the roof deck, sitting over a room or a garage, with a door opening onto it. The same threshold question applies, and a balcony over the garage ceiling will show its leak as a stain on that ceiling long before anyone upstairs notices.

The ground floor

Does the ground floor of a Houston townhouse flood?

It is the floor that would, and it is usually a garage plus 1 bedroom and a bathroom, sometimes a small den. Whether the lot is in a mapped floodplain is a question for the flood maps, not the listing. Harris County's maps were substantially revised after Hurricane Harvey in August 2017, and a good number of inner-loop lots that were outside the floodplain when the row was permitted are inside it now. Look up the address on FEMA's map service and on Harris County Flood Control District's tools before you make an offer, and read how the floodplain rules change what can be built if it comes back inside.

A lot outside the floodplain is not a lot that stays dry. Streets in parts of the inner loop are designed to hold water in a heavy storm. Walk the block and look at where the garage floor sits relative to the gutter. If the drive slopes down from the street into the garage, water has a path in.

What should I look for in the slab?

Houston sits on expansive clay, called gumbo, which swells when wet and shrinks when dry. New townhouses are almost all on post-tension slabs, which handle that movement well when they are built and drained properly. What you are looking for is evidence of movement at the joints between units: cracks that run diagonally from the corners of doors and windows, doors on the ground floor that stick or will not latch, and gaps opening where one unit's wall meets the next. Our longer piece on how gumbo clay moves Houston houses explains which cracks matter.

Look at the drainage around the building too. Rows of townhouses sit close together with narrow side yards. If the ground slopes toward the slab, or downspouts empty against the foundation, that water is working on the clay under the house every time it rains.

Check the base of the exterior walls for termite tubes. Subterranean and Formosan termites are a continuing problem here, and the space between 2 closely built units is exactly the damp, shaded gap they like.

The paperwork

Who owns the shared driveway?

This is the question buyers skip, and it is the one that causes the longest arguments. Many rows are built with a single shared drive serving 3, 4 or 6 garages. Sometimes that drive is a separate lot owned in common, sometimes each owner holds a strip with easements over the neighbours' strips, and sometimes there is a small owners' association with a budget. Each arrangement puts the cost of resurfacing, drainage repairs and gate maintenance in a different place.

Ask the title company for the recorded plat and any declaration or access agreement, and read who pays for what. Look for rules on parking in the shared drive, trash bins and exterior changes. The same goes for the deed restrictions on the underlying subdivision, which in the City of Houston do much of the work that zoning does elsewhere. We covered what deed restrictions actually control in a separate article.

Do I need an architect or engineer to look at a townhouse before I buy?

Usually not. That is an honest answer from a site that lists architecture firms. A licensed inspector with the Texas Real Estate Commission will catch most of what is on this page, and a structural engineer is worth calling only if the inspector flags foundation movement. Where an architect earns a fee on a townhouse purchase is when you plan to change it: adding an elevator, enclosing a roof deck, or reworking a floor. Then you want someone to look at the structure and the permit history before you commit, and our register of Houston architecture firms is the place to start.

One more check worth making. Texas has no state licence for residential general contractors, so the builder named on the sales paperwork has not passed any state exam. That does not make them bad. It does mean their track record is the only evidence you have, and how to check a builder when there is no licence to look up sets out what to ask for.

Where I would still buy one

None of this is an argument against the type. A 3-story townhouse is, for a lot of people, the only realistic way to live inside the Loop with a garage and a yard's worth of outdoor space on the roof. Plenty of them are built well. The builders who do it well tend to be consistent across every house in the row, which is why a quick look at an older row by the same builder is worth half an hour on a Saturday.

If your offer depends on changing the layout, run the numbers through our cost calculator before you sign, so the price of the house and the price of making it work are one figure, not two.