diff --git a/src/CryptoNoteCore/Currency.h b/src/CryptoNoteCore/Currency.h
index 64ebd7a6..38c44025 100644
--- a/src/CryptoNoteCore/Currency.h
+++ b/src/CryptoNoteCore/Currency.h
@@ -341,7 +341,7 @@ class CurrencyBuilder : boost::noncopyable {
   CurrencyBuilder& upgradeHeightV6(uint64_t val) { m_currency.m_upgradeHeightV6 = val; return *this; }
   CurrencyBuilder& upgradeHeightV7(uint64_t val) { m_currency.m_upgradeHeightV7 = val; return *this; }  
   CurrencyBuilder& upgradeVotingThreshold(unsigned int val);
-  CurrencyBuilder& upgradeVotingWindow(size_t val) { m_currency.m_upgradeVotingWindow = val; return *this; }
+  CurrencyBuilder& upgradeVotingWindow(uint32_t val) { m_currency.m_upgradeVotingWindow = val; return *this; }
   CurrencyBuilder& upgradeWindow(size_t val);
 
   CurrencyBuilder& transactionMaxSize(size_t val) { m_currency.m_transactionMaxSize = val; return *this; }