One of the worst mistakes self-storage owners and developers make on their first new build is going to their engineer without a rough sketch for their site plan. In many cases, they simply tell the engineer to do whatever makes sense and gets them the most rentable square footage. This is a bad idea unless you don’t mind racking up hours of billing and wasting everyone’s time.

There may be times when the municipality doesn’t even require a formal site or drainage plan from an engineer. That doesn’t mean you should forego establishing a clear vision for how your facility should be situated on the property. Even if professional help isn’t mandatory, I highly recommend that you pay an engineer to draw a plan.

But before you approach this person, it’s always good to take some ownership of the self-storage design and understand a few key principles that can streamline the process and help you arrive at an optimal outcome. Following are five important steps toward evaluating your property and sketching out a site plan.

1. Walk and Map the Site

Physically walk the site with a survey map, if possible, as well as the help of a smartphone app that has GPS tracking. If you’re building on vacant land, it’s often difficult to tell the exact boundaries, so this’ll give you a real lay of the land. Google Earth and onX Hunt are two mobile applications that allow you to see your position on a parcel while also experiencing the elevations with topography maps.

While walking the boundaries, you may notice things such as encroaching buildings, well, septic, utilities and other items that aren’t identified on the survey or parcel map. While your engineer should also do this, it’s sometimes better to discover any obstacles beforehand.

For example, I once found a septic field from a neighboring lot that encroached on our parcel. It was 30 feet off from where the survey indicated. Relocating it was a necessity and an additional cost we hadn’t anticipated. In fact, we had to delay our site plan until the matter was resolved, which likely was an even greater cost because it set back our municipal approval by almost a month.

2. Place the Driveway

Figure out where you’re going to put the entrance driveway. This is important, especially as the location that makes the most sense from the perspective of maximizing square footage isn’t always what the municipality, health department or department of transportation want. Officials often want your driveway to be directly across the road from another driveway, even if that means it’ll go right through the middle of your lot.

Driveway placement can make a huge difference because if you’re forced to build shorter self-storage buildings vs. fewer longer buildings, your construction costs can go up significantly. It may even make the site unfeasible. If this happens, you need to request a variance. In some jurisdictions, the driveway permit is separate from the zoning, so you really need both before you can start building. There’s no point in placing buildings without knowing where customers will enter the property.

3. Locate Utilities

It’s important to know where all the utilities are located including electric poles and fire hydrants. These can be difficult to see on a computer, which is why it’s important to walk the property in person. You may have to move them if they’re in the way of what you want to build. Cost may also dictate that you need to relocate your buildings or driveways to accommodate the utilities.

For example, I have a construction site where an electric pole was in the middle of the driveway we wanted to build. When we asked the city if we could alter the site plan and move the driveway, the only other location they would approve would’ve required us to split buildings in half. This would have been much more costly than paying $10,000 to move the utility pole, so we opted for the latter.

4. Understand Site Drainage

A reputable engineer who’s familiar with your market should be able to tell you ahead of time the soil structure of your self-storage property. This is important to know early because the composition of the soil will largely determine the costs to help it drain properly. If you see a lot of areas with pooling water and it hasn’t rained for days, you could have poor drainage or, worse, the presence of wetlands on site.

You want to see firsthand how well the site drains on its own before you start excavating. In my experience, assuming you don’t have to import or export a lot of soil, you can typically excavate a site with lots of sand for around $40,000 to $60,000 per acre. On a site with lots of clay or elevation, you may pay as much as $150,000 an acre, so understanding and identifying drainage issues early can determine whether your site is feasible.

5. Orientate Buildings to Site Conditions

Your goal should be to position your self-storage buildings in such a way that you optimize drainage and sunlight. If you’re in a cold climate, you almost always want to place them so they point north-south to lessen ice buildup on the north face.

Of course, sometimes the topography of the land, property dimensions or orientation of existing structures won’t allow you to lay out the facility as you’d like. If this is the case, try to factor all these items discussed to maximize the drainage, sunlight and amount of storage you can fit on site.

Sketching a Layout

Once you’ve completed the above steps, print a parcel map and try to draw a rough sketch of the self-storage layout as close to scale as possible. In determining building sizes, it helps to have an idea of your desired unit mix and what percentage of each size you plan to include. In a traditional design, we try to do 40-foot-wide buildings, but sometimes structures with 30-foot widths are needed because market demand dictates smaller unit sizes.

Unit sizes. When planning the unit mix, I try to keep all the units on both sides of each building to as few spaces as possible. This makes it easier for the labor that’ll eventually erect the steel. For example, if I have a building that’s 40 feet wide by 200 feet long, I could do all 10x20s on both sides. On another building, I could do all 10x10s and 10x30s, and then plan for 10x15s and 10x25s for another structure.

If I need to incorporate smaller units, I try to use the gable ends for 5x10s or extra 10x10s. In these instances, I try to use only one gable end for the units, so I can have the electrician install a box on that end wall. If that doesn’t pan out, a workaround is to convert a 5x10 unit into an electrical room, but keep in mind that’ll result in lost income.

Drive aisles. The industry standard for drive aisles is 30 feet wide, but if you have high land costs and smaller units, you may need to go with less. As a rule of thumb, don’t go narrower than the total depth of the units on both sides of the driveway. I prefer to be 25% to 50% wider than the unit depth, unless you’re building boat/RV storage. In that case, you want to be twice as wide as the depth of the units. For example, if my unit depth is 30 feet, the narrowest driveway you should go with is 30 feet. However, if land and building costs allow, I’d recommend pushing the width to 37.5 to 45 feet.

The reason for this is somebody may store a 20-foot boat or car in their unit, but they may be towing it with a 20-foot truck. They need space to maneuver around your facility to get items into their unit. If the space is tight, there’s a good chance they’ll run into your buildings, so don’t put customers in situations that increase the likelihood.

When plotting driveway width as well as the length and width of buildings in a sketch for your engineer, you don’t need to include the breakdown of the unit mix. However, you want to make sure the actual building measurements are correct because that’s how the engineer will plan the drainage.

If you can provide a sketch to scale for your engineer, you’ll save them a ton of time because they’ll at least have a strong idea of what you’re looking for and can use it as a launching pad for formal site planning. Once you’ve completed all these steps, you’ll be well on your way to developing an optimal site plan for your new self-storage property.

Charlie Kao is the principal of Twin Oaks Capital, a Michigan-based commercial real estate company specializing in self-storage and multi-family assets. Services include real estate brokerage, asset management, feasibility studies, consulting and building-construction management. The company and its affiliates have owned, operated or planned more than 1 million square feet of self-storage. Charlie also owns House of Kaos Real Estate School, which provides continuing education credits for licensed realtors. He can be reached at [email protected].