Prepared for Jan de Vries · Elandsgracht 77, Amsterdam
Plan date 17 June 2026
Reference SND-2026-0382
Advisor M. Hendriks
F current
→C projected
Your prioritised upgrades
1
Cavity Wall Insulation ISDE subsidy
Insulation beads injected into the wall cavity. One-day job, no interior disruption. The highest-impact first step for a label F property, cutting heat loss through the walls by up to 60%.
Est. cost
€3,200
Saves / yr
€480
Payback
6.7 yrs
ISDE subsidy
–€800
ISDE 2026: apply within 24 months. Budget round closes 31 Dec 2026.
2
Floor Insulation ISDE subsidy
Spray foam under the wooden floor joists. Two-day job with minimal disruption. Combined with the cavity walls, eliminates the majority of the building's heat loss.
Est. cost
€2,800
Saves / yr
€350
Payback
6.5 yrs
ISDE subsidy
–€700
ISDE 2026 floor allowance. File alongside measure 1 for a combined submission.
3
HR++ Double Glazing
Replace single-glazed windows (street-facing) with HR++ units. Essential for comfort and closing the gap to label C.
Est. cost
€4,800
Saves / yr
€320
Payback
15 yrs
Subsidy
—
No standalone subsidy. Combining with measures 1–2 raises the overall insulation allowance.
Recommended sequence
1
AUG 2026
Cavity wall insulation
1 day on site · do this first
2
SEP 2026
Floor insulation
2 days on site
3
OCT 2026
HR++ glazing
2–3 days on site
✓
NOV 2026
Inspection & claim
New label registered: C
Total investment
€10,800
Net after subsidies
€9,300 (–€1,500)
Annual savings
€1,150/yr
Blended payback
8.1 yrs
Ready to move forward?
Book a 30-minute call with your SUNDAE advisor to confirm this plan and kick off works.