Cold email case study: why architects called instead of replying

Over one year, cold emails brought Pilotech, an air conditioning installer near Paris, 15 new clients. This cold email case study shows how the campaigns were built: who they targeted, what the emails looked like, and what happened once they went out.

The emails went to three audiences: Paris restaurants, Paris offices and shops, and architects. Architects were the main focus, and they produced the result I had not planned for. Many of them did not reply. They called.

The website and SEO side of the story is in the Pilotech SEO case study. Here I stay with the emails: the set-up, the numbers I can share, why I think architects picked up the phone, and what we changed once we saw it.

The client, the offer and the three audiences

Pilotech installs air conditioning, heat pumps and ventilation for homes and businesses in Paris and the Île-de-France. It is a small company: the founder runs it and does the selling, with two full-time employees and subcontractors. I have worked with him for two years, on the websites, the SEO and the cold emailing.

It has a rare speciality: Teknopoint air conditioning with no outdoor unit, for buildings where a unit on the façade is not allowed, such as Haussmann-era and listed buildings. Before these campaigns, Pilotech had never approached Paris businesses directly. The Pilotech Teknopoint project page describes the website and the campaign.

The emails carried one offer: a free technical visit and a firm quote, for an installation that cannot be seen from the street. The founder told me which clients he wanted, and I went looking for the right leads. I do everything in a campaign except the replies: those go to the client.

Why architects were the main target

A restaurant, an office or a shop buys air conditioning for its own premises. An architect specifies it for one client project after another, and chooses, or at least recommends, the company that installs it. For an installer, an architect who trusts you can bring more than one job.

The architects on the list were mostly of two kinds:

• solo architects carrying large projects, such as sixteen units to install in a hotel;
• heads of architecture firms.

Most worked in Paris. Once, an architect based in Toulouse wanted to work with Pilotech too.

Pilotech’s speciality also answers a problem architects meet in Paris: buildings where a unit on the façade is not an option. If you sell to the building trade, marketing to architects follows the same logic: reach the person who specifies, and make it easy for them to talk to you.

The set-up: a clean list, 30 addresses, three plain-text emails

A verified list from private sources

I keep my lead sources to myself, but the cleaning step is no secret: the list went through Reoon, the email verifier I use every day, before the first send. A dead address bounces, and bounces wear down the reputation of the addresses you send from. The steps are in how I verify an email list, and MLK Leadhunters explains where B2B leads usually come from in building a cold email list.

30 sending addresses

The emails went out from 30 addresses used only for cold email. Spreading the sending over many addresses keeps each one’s daily volume low, and if one address runs into trouble, the others carry on. My guide to cold email infrastructure uses this campaign as its worked example.

Three plain-text emails and a phone number

Each contact received three emails at most, in plain text: no links, no HTML, no images. I send plain text only, because it protects delivery. It also reads like what it is: a message from one person to another.

The first email is three lines at most: who is writing, the offer, and the call to action. People do not want long emails from strangers they never asked for anything. Short and sharp works.

The call to action is the phone. The number is written in the email, with an invitation to call and to look at the catalogue on the website, and there is no link anywhere. The emails were signed by the founder. The real emails stay private, but the first one had this shape:

Hello [first name],

[One line: who is writing, what the company installs and where.]
[One line: the offer, a free technical visit and a firm quote.]
[One line: the invitation to call, with the number, and to look at the catalogue on the website.]

[Founder's first name and surname], [company]
[phone number]

You will find complete first emails built this way in my cold email examples, and MLK Leadhunters covers the basics in how to write a cold email that gets replies.

The third email matters more than people think. It still brings positive replies, from people who had forgotten the first two or had no time to answer them. I explain why I stop at three in my guide to cold email follow-ups.

The results: 15 new clients in a year

Over a year, the campaigns brought Pilotech 15 new clients. I do not publish what the contracts were worth: that stays between Pilotech and its clients.

The results did not show up where a campaign dashboard looks for them. Written replies went straight to the founder, who answered them himself from his own inbox. And many prospects, architects especially, did not write back at all: they called the number in the email.

Cold email is one of several channels working for Pilotech. Together, the websites, SEO and cold email now bring it about ten prospects a day. At one point there were more prospects than the team could follow, and the founder asked me for an internal app that gathers every prospect in one place, so that no call-back is missed.

Why architects called instead of replying

My reading, after a year of these campaigns, comes down to four reasons.

1. A call is faster. People do not have time. They call the moment they have a minute, while a written answer waits for a quiet moment at a desk.
2. Emails get buried. A reply put off until later sinks under the rest of the day’s emails.
3. Calling is like ticking off a to-do list. One call and the item is done, with no thread to follow.
4. People like real human contact. A conversation with the person behind the offer feels more natural than a written exchange with a stranger.

What we changed once we saw it

We did not fight it: we made calling even easier in the sequences. Written replies kept going to the founder, and so did the calls, since the number in the emails was his.

This is the part most campaign plans miss. If your call to action is a phone number, someone who can sell has to answer that phone, and quickly. MLK Leadhunters’ article on what to do with replies covers the hour after a prospect answers, and the same rules apply to a call. I compare the two channels in cold calling vs cold emailing.

Lessons from this cold email case study

What I would keep for any small business that sells to other businesses:

1. Aim at the people who specify, not only at the people who buy: one relationship can be worth several jobs.
2. Treat the email as the introduction and the phone as the conversation. Put the number in the email, invite people to use it, and make sure someone who can sell picks up.
3. Keep the emails short and plain, and do not stop too early: three lines, no links, no HTML, and a third email for the people who were simply busy.

The whole process, from the offer to the replies, is in my B2B cold emailing guide.

Before you email architects yourself: a checklist

If you install, build or supply for building projects and want to try this with architects, check each point before the first send:

1. Your offer fits in one line. Pilotech’s was a free technical visit and a firm quote.
2. Your list holds only architects, with a separate sequence for any other audience, and every address is verified.
3. You send from dedicated, warmed-up addresses, never from your main mailbox.
4. Every email names the sender and offers a simple way to opt out, such as a line inviting people to reply if they want no more emails. The rules differ between the UK and France: my cold email GDPR checklist covers both.
5. You never write again to anyone who said no.
6. You know who answers the phone and the written replies, at what hours, and that person notes where each call came from.

You do not need an agency for this. With one audience, a verified list and the time to answer every reply and every call, you can run a campaign like this yourself with a sending tool. If you would rather hand over everything except the conversations, that is how MLK Leadhunters works: the studio’s cold email practice finds the leads, writes and sends the emails, and leaves the replies and the calls to you.