In our new founder interview series, we take you behind the pitch decks and prototypes – into the stories of the people shaping the future. We explore the sparks, doubts, and turning points that define early-stage building.

Today’s guests: Marie Roels & Belén Martínez – Co-Founders of MARCH. Marie is an award-winning architect who’s swapped studio life for a CEO seat; Belén is a trilingual growth strategist who’s opened markets on three continents. Together they’re building MARCH, a B2B2C SaaS platform that cuts the friction out of green construction—matching eco-minded clients with sustainable architects and the right materials in minutes. In this short interview they unpack the carbon hiding in every brick and door, the serendipitous client-turned-co-founder story, and why real change in construction starts with tactile materials, shared mantras (“we’re doing great!”), and a few late-night VAT invoices.

What pulled you into architecture?

Marie: I decided early on to go for this combination of creativity and problem-solving—but also the very practical, hands-on experience of literally building something.
Belén: It was not planned. I like to do a lot of different things… out of luck I started working in the architecture world and I really liked design.

 

Why did you choose to focus on materials?

Marie: I’ve always been inspired by materiality—the things you can touch. But for me it’s about the tactility of sustainable materials; they have so much more fibres and texture.
Belén: If we want to make a change around sustainability, focusing on the materials is key. People don’t think about the door—what wood is that door made of?—but it can affect the environment.

 

Biggest “oh sh*t” moment?

Marie: Charging our first clients—setting up our first invoice and the VAT number—I remember we were like, we need to get our ducks in a row right now.
Belén: For me it was signing at the notary to incorporate the company. We made the guy print the papers four or five times, asked for a latte macchiato… and the notary was like are you kidding? We were there like 4 hours the whole afternoon. Sometimes you are in a really like serious situations and we were like just taking pictures and we ware asking the notary, “Could you take a picture for us please?” 🙂

 

Weirdest or funniest moment while building MARCH?

Marie: I was with a potential customer and I explained MARCH and the company and everything and then she asked, “oh like how long have you been doing this?” And said, we’re really out here for a couple of months. And then she said, “Oh, I actually know your brand, and I know your company, and I’ve seen you around, so I thought you were doing this for like two, three years.”

Then I though, oh, wow – amazing. That’s amazing! We must be doing something good.


Belén: At the beginning we kept cutting each other off in meetings, trying to add things the other forgot. Now we’ve learned to let each other be.

 

Small moments that keep you going?

Belén: For me, what helps has been the in-person events and speaking with people and seeing that you are not alone in the trip and that also people struggle. When other co-founder comes and tells you, “yeah, this is hard!” And yes, it’s true, sometimes it is hard! Or you tell the idea and another person that doesn’t know anything about you says, “oh, this idea is cool.” So I really appreciate other co-founders feedback or experts when they say that the idea is really good and that they see a lot of potential. It’s like, “okay, let’s go, we can do this!”


Marie: “When customers get excited and you leave the call full of energy… And having a co-founder who has your back—then I know I’m in the right place.”

 

What about advice you would have loved to receive earlier?

Belén: Don’t worry about people who don’t understand—keep on, you are doing great.
Marie: I think for me it’s like this notion of when you’re a founder you need to be extraordinary, you need to be very good at stuff. But I feel like when you share vulnerability that’s when you also learn the most. So I think just not trying to be too perfect.

 

Startup myth you’d like to debunk?

Belén: That you need to know everything and be perfect but it’s impossible to know everything. Just do it, you will learn on the way. If you do it wrong you will do it better next time. 
Marie: Being the only architect in the room can actually help; those creative problem-solving skills translate.

 

Your founder super-powers?

Belén: I really like our team because I think we are two people that like to do things. We don’t think too much about them, we just try! We are real problem solvers, we are action persons, we do things and then we see how they worked out and I have seen that that’s essential for a founding team.
Marie: Yeah sometimes I feel like our team is actually our super power!

 

Describe your co-founder in one word

Belén on Marie: Amazing.
Marie on Belén: Structured… and spontaneous – she makes friends everywhere.

 

Most over-used startup word right now

Marie: Disruption – especially in construction.
Belén: Empower – it’s used so much it’s losing meaning!

 

One piece of fundraising advice?

Belén: Speak with everyone. You never know where the money can come from.
Marie: It’s never too early to talk to investors; you don’t need a pitch deck to start a conversation. When you’re really early but an investor reaches out, don’t waste weeks on preparing the perfect pitch deck, on setting up data and financial modeling. Just talk to them. Talk about your validation, where you are, about your passion and your vision.

I think that’s really enough to grab their attention and make them want to come back in a couple of weeks or a couple of months when you are ready with a pitch deck.

I think actually a lot of investors, they appreciate when you’re just having a conversation about something that you’re passionate about. And they will fall in love with you and with the idea. Not with the solution.