This One Mistake Puts Roofing & HVAC Owners at Higher Risk of Cash Flow Problems

“I still can’t figure out why our bank account always feels drained.”

"Mareaka, we’re booked solid for the next six weeks—repairs, installs, even some commercial work—but I still can’t figure out why our bank account always feels drained. We’re doing more jobs than ever, but the cash just isn’t there. What gives?"

That question comes up more than you’d think. You might be booking jobs, staying busy, and even hitting solid revenue numbers—but still struggling to make payroll or cover materials without dipping into personal funds.

Here’s the truth: Revenue doesn’t equal profit. And profit doesn’t always mean cash in your hand.

So let’s dig into the one mistake that puts a lot of roofing and HVAC owners at risk—and how to fix it.

The Mistake: Spending Before the Cash Hits Your Account

It sounds simple, but it’s the #1 reason even successful contractors run into money problems. You get excited about landing new jobs, so you start:

Buying materials (maybe $8,000 upfront for shingles, HVAC units, or sheet metal before the job even starts)
Hiring extra help (bringing on a temp crew for $1,500/week)
Paying subs (cutting checks for $3,000 before you’ve been paid a dime)
Upgrading tools or trucks (dropping $25K on a new work van because you expect jobs to cover it)

All before the first check clears.

Then, delays happen.

Customer takes 30-60 days to pay (on a $20,000 job, that means you're waiting up to two months to see that money)
Your crew takes longer than expected (a 3-day install turns into 5, adding two extra days of labor at $500/day)
You underestimated how much cash you’d need to front (thinking you'd need $5,000 to start the job but ending up spending $9,000 before the first draw comes in)

Now you’re in a hole—about $15,000 to $20,000 in the red when you add up materials, labor, and that new van—and even though the money should be coming, you might not see it for another 30 to 60 days.

That’s a long time to be floating expenses and scrambling to cover payroll or the next job’s deposit.

This creates a cycle where you’re always chasing cash, not planning ahead.

How to Fix It Before It Drains Your Business

So how do you break the cycle?

Here are three key strategies I’ve helped clients implement that have turned things around fast—and you can start using them to keep your business cash-healthy year-round:

1. Improve Invoicing & Collections

Invoice faster: Send invoices as soon as work is done, not at the end of the week or month. That means the minute your crew finishes a job, you’re hitting “send” on the invoice—ideally while your team is still packing up. For example, if you wrap up a $12,000 HVAC install on Thursday afternoon, don’t wait until Monday to bill it out. Get that invoice out same-day while the customer still remembers the value of what you delivered. The sooner it hits their inbox, the sooner you get paid—and that might mean getting paid 3 to 5 days earlier on average per job, which adds up big over a month.

Use milestone payments: For big jobs, bill in phases (start, midway, completion).

Follow up like clockwork: Don’t wait weeks to chase unpaid invoices. Use automated reminders or assign someone to stay on top of it.

Even shaving a few days off payment time can make a big difference in your cash position.

2. Forecast Your Cash Flow

You don’t need to be an accountant to forecast cash flow. Start with a basic spreadsheet or app:

List out your expected income by week
List your recurring and one-time expenses
See where the gaps are before they hit

This gives you time to delay a purchase, push out a payment, or line up a short-term job to fill the gap.

Pro tip: Don’t just look at this month—forecast 30, 60, and 90 days out.

3. Manage Expenses with a Proactive Plan

When cash feels good, it’s easy to overspend. So create rules for yourself:

Only spend a percentage of deposits upfront: For example, if you get a $10,000 deposit, plan to use just $5,000–$6,000 to start the job. This gives you breathing room in case timelines shift or payments are delayed.

Wait to upgrade equipment until payment hits: One client was eyeing a $15,000 equipment upgrade but waited until a $40,000 check actually cleared. That one decision kept them from having to float payroll the following week.

Have a baseline reserve (like one month’s expenses) to cover dips: Let’s say your overhead—including rent, payroll, and vendor costs—runs $25,000/month. That means keeping $25K in reserve gives you the cushion to survive slow weeks, delayed payments, or emergency repairs without scrambling.

If you treat your bank account like a project schedule—with planned phases and built-in buffer—you’ll avoid that panicked "how are we going to cover payroll?" moment.

One of my HVAC clients had back-to-back installs booked and was thrilled about the revenue. But between materials, labor, and a few late payers, he was burning through his line of credit by week three.

We reworked his invoicing to include 40% upfront, 40% mid-job, and 20% on completion. We also created a simple forecast to spot slow weeks in advance.

That one change flipped his cash position from stress to surplus in under two months.

Don’t Let Busy Season Bury You

Just because you're booked out doesn’t mean your bank account should be empty.

If you’re constantly hustling but never feel ahead, it’s time to shift how you handle cash.