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    <element name="VendorRelatedMember" id="iesc_VendorRelatedMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
    <element name="The2015StockRepurchaseProgramMember" id="iesc_The2015StockRepurchaseProgramMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
    <element name="OffMarketPocAdjustmentMember" id="iesc_OffMarketPocAdjustmentMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
    <element name="PhantomshareunitspsusperformancebasedMember" id="iesc_PhantomshareunitspsusperformancebasedMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
    <element name="TwoThousandSixEquityIncentivePlanMember" id="iesc_TwoThousandSixEquityIncentivePlanMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
    <element name="AvailableCommonStockAuthorizedShares" id="iesc_AvailableCommonStockAuthorizedShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="instant" />
    <element name="OwnershipPercentageOfCommonStock" id="iesc_OwnershipPercentageOfCommonStock" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="instant" />
    <element name="RecognizedBenefit" id="iesc_RecognizedBenefit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration" />
    <element name="PerformanceCashUnitsMember" id="iesc_PerformanceCashUnitsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
    <element name="CapstoneMember" id="iesc_CapstoneMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
    <element name="UnrestrictedStockMember" id="iesc_UnrestrictedStockMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
    <element name="ResidualSharesRelatedToAcquisitionReturnedToTreasuryStock" id="iesc_ResidualSharesRelatedToAcquisitionReturnedToTreasuryStock" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
    <element name="Netincomelossattributabletoparentavailabletocommonstockholdersbasic" id="iesc_Netincomelossattributabletoparentavailabletocommonstockholdersbasic" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration" />
    <element name="Netincomelossattributabletoparentavailabletocommonstockholdersdiluted" id="iesc_Netincomelossattributabletoparentavailabletocommonstockholdersdiluted" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration" />
    <element name="FreemanAcquisitionMember" id="iesc_FreemanAcquisitionMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
    <element name="SeriesOfBusinessAcquisitions2017MemberMember" id="iesc_SeriesOfBusinessAcquisitions2017MemberMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
    <element name="ContractRevenueEarnedToDate" id="iesc_ContractRevenueEarnedToDate" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant" />
    <element name="UsamriidmemberMember" id="iesc_UsamriidmemberMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
    <element name="BusinessacquisitionnextmemberMember" id="iesc_BusinessacquisitionnextmemberMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
    <element name="BusinessacquisitiontechnicalservicesmemberMember" id="iesc_BusinessacquisitiontechnicalservicesmemberMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
    <element name="Seriesofbusinessacquisitions2018membermemberMember" id="iesc_Seriesofbusinessacquisitions2018membermemberMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
    <element name="IndustrialServicesMemberMember" id="iesc_IndustrialServicesMemberMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
    <element name="CustomPowerSolutionsMemberMember" id="iesc_CustomPowerSolutionsMemberMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
    <element name="SingleFamilyMemberMember" id="iesc_SingleFamilyMemberMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
    <element name="MultiFamilyMemberMember" id="iesc_MultiFamilyMemberMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
    <element name="Estimatedprofitoncontractsinprocess" id="iesc_Estimatedprofitoncontractsinprocess" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" />
    <element name="Billingstodate" id="iesc_Billingstodate" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant" />
    <element name="Contractsinprocessnet" id="iesc_Contractsinprocessnet" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" />
    <element name="PerformanceObligations" id="iesc_PerformanceObligations" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" />
    <element name="RevenueRecognizedOnContractLiabilities" id="iesc_RevenueRecognizedOnContractLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration" />
    <element name="PerformanceObligationNext12Months" id="iesc_PerformanceObligationNext12Months" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" />
    <element name="ProceedsPaymentContingent" id="iesc_ProceedsPaymentContingent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" />
</schema>
