Together with his stepbrother Abraham Winands, Tessin actively took part in his father's work, and when Tessin inherited his father's position, he asked to share it with Winands and the two would keep working side by side until the death of Winands in 1709.
Spolu s nevlastným bratom Abrahamom Winandsom sa Tessin zúčastnil na otcových dielach, a keď Tessin zdedil otcove miesto, požiadal o povolenie zdieľať toto miesto spolu s Winandsom, s ktorým pracoval bok po boku až do roku 1709, keď Winands zomrel.