Goodwill and Other Intangible Assets
Goodwill
The following are the changes in the carrying value of goodwill:
(Millions of US dollars)EuropeSiding & TrimDeck, Rail & AccessoriesTotal
Balance - March 31, 2024
$192.6 $— $— $192.6 
Foreign exchange impact1.1 — — 1.1 
Balance - March 31, 2025
$193.7 $— $— $193.7 
Foreign exchange impact11.3 — — 11.3 
Acquisition of The AZEK Company— 1,141.2 3,434.2 4,575.4 
Balance - March 31, 2026
$205.0 $1,141.2 $3,434.2 $4,780.4 

Intangible Assets
The following are the net carrying amount of indefinite lived intangible assets other than goodwill:
 March 31
(Millions of US dollars)20262025
Trade names$118.2 $111.6 
Other7.4 7.4 
Total$125.6 $119.0 
The following are the net carrying amount of amortizable intangible assets:
March 31, 2026
(Millions of US dollars)Lives in YearsGross Carrying AmountAccumulated AmortizationNet Carrying
Amount
Customer Relationships
2 to 18
$2,880.3 $(165.8)$2,714.5 
Trade Names
5 to 15
$330.0 $(19.6)$310.4 
Technology
10
$210.0 $(20.4)$189.6 
Total$3,420.3 $(205.8)$3,214.5 
March 31, 2025
(Millions of US dollars)Lives in YearsGross Carrying AmountAccumulated AmortizationNet Carrying
Amount
Customer Relationships
2 to 13
$47.5 $(20.9)$26.6 
Total$47.5 $(20.9)$26.6 
The amortization of intangible assets was $183.6 million, $4.4 million and $4.3 million for the fiscal years ended March 31, 2026, 2025 and 2024, respectively. As of March 31, 2026, the remaining weighted average amortization period for acquired intangible assets was 16.7 years.
At March 31, 2026, the estimated future amortization of intangible assets is as follows:
Years ended March 31 (Millions of US dollars):
Fiscal 2027
$315.4 
Fiscal 2028
332.2 
Fiscal 2029
345.5 
Fiscal 2030
332.5 
Fiscal 2031
295.2 
Thereafter1,593.7 
Total$3,214.5 

About Goodwill & Intangibles Disclosures

Goodwill and intangible asset disclosures reveal the premium paid in acquisitions and how management assesses whether that premium retains its value. Since goodwill is no longer amortized under US GAAP, the annual impairment test is the only mechanism that adjusts carrying values downward — making the assumptions behind that test critically important for investors.

Key signals: a history of goodwill impairments suggests management consistently overpays for acquisitions. Watch the gap between reporting unit fair value and carrying amount — when fair value exceeds carrying amount by less than 10-20%, a small decline in business performance could trigger a write-down. For finite-lived intangibles, examine useful life assumptions across customer relationships, technology, and trade names; aggressive estimates inflate near-term earnings. Compare total intangibles-to-total-assets ratios against peers to assess acquisition dependency. Rising goodwill as a percentage of equity can signal balance sheet fragility.